Outboard jet drive marine propulsion system and control lever therefor

Abstract

A jet pump for an outboard propulsion marine engine includes a support member and at least one impeller blade extending helically from said support member At least one induction blade extends helically from said support member. A stator having a volume reduction member is disposed downstream of the blades. The jet pump is supported in a housing having a stepped profile to reduce drag. A single lever controls both the speed and direction of the jet stream exiting the stator.

1 . A jet pump for an outboard propulsion marine engine comprising: 
 a support member;    at least one impeller blade extending helically from said support member; and    at least one induction blade extending helically from said support member.    
   
   
       2 . The jet pump of  claim 1 , wherein each of said at least one impeller blades has a width, and each of said at least one induction blades has a width less than the width of each of said at least one impeller blades.  
   
   
       3 . The jet pump of  claim 1 , wherein each of said at least one induction blades has a length, each of said impeller blades has a length, said length of each said at least one induction blades being less than the length of each of said at least one impeller blades.  
   
   
       4 . The jet pump of  claim 1 , wherein each induction blade has a leading edge and a trailing portion, the pitch of said leading edge being less than the pitch of said trailing portion.  
   
   
       5 . The jet pump of  claim 1 , wherein each impeller blade has a leading edge and a trailing portion, the pitch of said leading edge being less than the pitch of said trailing portion.  
   
   
       6 . The jet pump of  claim 1 , wherein said support member is conical.  
   
   
       7 . The jet pump of  claim 1 , wherein said induction blades are disposed on said support member upstream of said impeller blades.  
   
   
       8 . The jet pump of  claim 1 , wherein said at least one induction blade defines a plurality of induction blades and said at least one impeller blade defines a plurality of impeller blades, at least one induction blade being disposed between at least two of said plurality of impeller blades.  
   
   
       9 . The jet pump of  claim 7 , wherein said plurality of impeller blades includes at least four impeller blades.  
   
   
       10 . The jet pump of  claim 2 , wherein each of said at least one induction blades has a length, each of said at least one impeller blades has a length, said length of each said at least one induction blades being less than the length of each one of said at least one impeller blades.  
   
   
       11 . The jet pump of  claim 2 , wherein each induction blade has a leading edge and a trailing portion, the pitch of said leading edge being less than the pitch of said trailing portion.  
   
   
       12 . The jet pump of  claim 2 , wherein said induction blades are disposed on said support member upstream of said impeller blades.  
   
   
       13 . The jet pump of  claim 4 , wherein each impeller blade has a leading edge and a trailing portion, the pitch of said leading edge being less than the pitch of said trailing portion.  
   
   
       14 . The jet pump of  claim 1 , further comprising a housing and a water exhaust formed within said housing, a stator disposed in said water exhaust downstream of said at least one impeller blade, said stator having a central member, a plurality of stator blades extending radially from said central member towards a wall of said housing; and 
 a volume reduction member extending from said central member downstream of said plurality of stator blades, for reducing the volume within said water exhaust without substantially interfering with a flow path of water passing from said stator blades.    
   
   
       15 . A jet pump for an outboard propulsion marine engine for use with a rigid inflatable boat comprising: 
 a support member;    at least one impeller blade extending helically from said support member; and    at least one induction blade extending helically from said support member.    
   
   
       16 . The jet pump for an outboard propulsion marine engine of  claim 15 , wherein each of said at least one impeller blades has a width, and each of said at least one induction blades has a width less than the width of each of said at least one impeller blades.  
   
   
       17 . The jet pump for an outboard propulsion marine engine of  claim 15 , wherein each of said at least one induction blades has a length, each of said impeller blades has a length, said length of each said at least one induction blades being less than the length of each of said at least one impeller blades.  
   
   
       18 . The jet pump for an outboard propulsion marine engine of  claim 15 , wherein each induction blade has a leading edge and a trailing portion, the pitch of said leading edge being less than the pitch of said trailing portion.  
   
   
       19 . The jet pump for an outboard propulsion marine engine of  claim 15 , wherein each impeller blade has a leading edge and a trailing portion, the pitch of said leading edge being less than the pitch of said trailing portion.  
   
   
       20 . The jet pump for an outboard propulsion marine engine of  claim 15 , wherein said support member is conical.  
   
   
       21 . The jet pump for an outboard propulsion marine engine of  claim 15 , wherein said induction blades are disposed on said support member upstream of said impeller blades.  
   
   
       22 . The jet pump for an outboard propulsion marine engine of  claim 15 , wherein said at least one induction blade defines a plurality of induction blades and said at least one impeller blade defines a plurality of impeller blades, at least one induction blade being disposed between at least two of said plurality of impeller blades.  
   
   
       23 . An outboard jet drive marine propulsion system having a housing and a water exhaust formed within said housing, said system comprising: 
 a stator disposed in said water exhaust, said stator having a central member, a plurality of blades extending radially from said central member towards a wall of said housing; and    a volume reduction member extending from said central member downstream of said plurality of blades, for reducing the volume within said water exhaust without substantially interfering with a flow path of water passing from said blades.    
   
   
       24 . The system of  claim 23 , further comprising a ring, said ring adapted to be received in said housing, said blades extending from said central member to said ring.  
   
   
       25 . The system of  claim 23 , wherein said housing includes a wall, said blades extending to said wall, said stator being integrally formed with said housing.  
   
   
       26 . The system of  claim 23 , wherein said central member is a conical member extending downstream from said blades.  
   
   
       27 . An outboard jet drive marine system for a boat comprising: 
 a housing, said housing having a front and rear sides, and a top and a bottom, said housing adapted to be affixed behind a hull of said boat;    an engine disposed within said housing; and    a jet drive unit mounted to said housing and being operatively coupled to said engine in said housing, said engine having an exhaust and cylinders, a turbocharger operatively coupled between said exhaust and said cylinders, said turbocharger having a housing for receiving said exhaust, a turbine assembly, said exhaust rotating said turbine assembly, said turbine assembly providing compressed air to said cylinders, said housing having a diameter, said diameter being dimensioned to control the exhaust gas volume and speed to optimize a turbine speed of said turbine assembly to reduce back pressure.    
   
   
       28 . The outboard jet drive marine system of  claim 27 , wherein said turbine assembly includes a first turbine disposed in said housing, said turbine rotating in response to exhaust from said engine, a shaft, a second turbine disposed in said housing coupled to said shaft so that said second turbine rotates with said first turbine, an air intake operatively communicating with said second turbine, said second turbine moving air from said air intake into said cylinders when rotating.  
   
   
       29 . The outboard jet drive marine system of  claim 27 , wherein said engine has an effective horsepower of more than about 200 horsepower.  
   
   
       30 . The outboard jet drive marine system of  claim 28 , wherein said boat is a rigid inflatable boat.  
   
   
       31 . The outboard jet drive marine system of  claim 29 , wherein said boat is a rigid inflatable boat.  
   
   
       32 . An outboard jet drive marine system for a boat comprising: 
 a housing, an engine disposed within said housing, said engine having an air intake;    a jet drive unit operatively coupled to said engine; and    a siphon tap provided along an inlet air passage of said engine for siphoning off a portion of air traveling through said engine under pressure, said boat being a rigid inflatable boat having inflatable structure, piping defining an air path extending from said siphon tap to at least one of said inflatable sections, a regulator disposed in the air path along said piping, said regulator opening when a downstream pressure falls below a predetermined level to allow inflation of at least one inflatable portion.    
   
   
       33 . The outboard jet drive marine system of  claim 32 , wherein said regulator releases air in the upstream air path direction if pressure of said at least one inflated sections exceeds a predetermined amount.  
   
   
       34 . A lever control for an outboard jet drive marine system for a boat, a water jet exiting said outboard jet drive marine system to move said boat, said system comprising: 
 a lever assembly movable between a first position and a second position, said lever operatively coupled to a shift, said shift controlling a direction of water jet exiting from said outboard jet drive marine system, said lever moving said shift in a first direction when said lever moves in said first direction between a first position and a second position and causing said water jet to exit said system in a first direction when said shift is in said first position and cause said water jet to exit said system in a second direction when said shift is in a second position.    
   
   
       35 . The lever control for an outboard jet drive marine system of  claim 34 , further comprising a throttle operatively coupled to said lever for controlling the speed of said jet when said lever is in said first position and for controlling the speed of said jet in said second direction when said lever is in said second position.  
   
   
       36 . The lever control for an outboard jet drive marine system of  claim 35 , wherein said lever moves between a second position and a third position, said throttle increasing the speed of said jet as said jet moves from said second position to a third position.  
   
   
       37 . The lever control for an outboard jet drive marine system of  claim 34 , further comprising a jet drive unit and an engine operatively coupled to said jet drive unit, said jet drive unit including an exhaust and a bucket, said shift being operatively coupled to said bucket and said throttle being operatively coupled to said engine.  
   
   
       38 . The lever control for an outboard jet drive marine system of  claim 37 , wherein said lever moves said shift to a fourth position located between said second and third position wherein said shift causes said bucket to balance the force of a water jet exiting said system in both the first direction and second direction.  
   
   
       39 . The lever control for an outboard jet drive marine system of  claim 34 , wherein said lever is a lever plate, said shift is a shift plate, said lever plate moving said shift plate in a first direction when said lever rotates in said first direction and a second direction when said lever rotates in said second direction.  
   
   
       40 . The lever control for an outboard jet drive marine system of  claim 39 , wherein said throttle plate is a throttle plate operatively coupled to said lever plate, said throttle plate controlling the speed of the jet in a reverse direction when said lever plate is in said first position and controlling the speed of said jet in a forward direction as said lever plate moves from said second position to said third position.  
   
   
       41 . The lever control for an outboard jet drive marine system of  claim 39 , wherein rotation of said shift plate causes said lever plate to selectively rotate said throttle plate in one of said reverse and forward directions.  
   
   
       42 . The lever control for an outboard jet drive marine system of  claim 34 , wherein said boat is a rigid inflatable boat.  
   
   
       43 . An outboard jet drive marine system for a boat comprising: 
 a jet unit; a housing, said housing having front and rear sides and a top and a bottom, said housing adaptively affixed behind a hull of said boat, said housing including a convex portion at its bottom curved in the direction extending from the hull of the boat in a direction away from the boat for guiding air bubbles away from the jet unit.    
   
   
       44 . The outboard jet drive marine system for a boat of  claim 43 , wherein said convex section has a pitch and a centerline, the pitch of said convex portion increasing in a direction away from said centerline.  
   
   
       45 . The outboard jet drive marine system for a boat of  claim 44 , wherein said pitch is between 0° and 26°.  
   
   
       46 . The outboard jet drive marine system for a boat of  claim 43 , wherein said hull has a substantially V-shape.  
   
   
       47 . The outboard jet drive marine system for a boat of  claim 45 , wherein said hull has a substantially V-shape.  
   
   
       48 . The outboard jet drive marine system for a boat of  claim 43 , wherein said boat is rigid inflatable boat.  
   
   
       49 . The outboard jet drive marine system for a boat comprising: 
 a jet unit, a housing, said housing having front and rear sides, a top and a bottom surface, said housing adapted to be affixed behind a hull of said boat; said housing including a centerline, a respective side on each side of said centerline including at least a first step portion to form a shelf, the step being sufficiently narrow to maintain the overall width of said housing less than a width of said boat to which said housing is adjacent.    
   
   
       50 . The outboard jet drive marine system for a boat of  claim 49 , wherein a pocket formed in said first step as a further step portion within said shelf, an engine disposed within said housing, said engine having an exhaust, a vent formed in said pocket and coupled to said exhaust for guiding gases away from the centerline when said engine moves in a reverse direction.