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AssigneeBrunswick Corporation
InventorsMichael A. Karls, Roger E. Koepsel, Ronald M. Steiner
Estimating the term…
A marine propeller includes a hub rotatable about a longitudinal axis and having a plurality of blades extending radially outwardly therefrom and pivotable about respective radial pivot axes between a low pitch position and a high pitch position. A disc has a plurality of guide slots each receiving and retaining a respective lever arm extending rearwardly within the hub from a respective blade. A biasing spring coaxial with the longitudinal axis of rotation of the hub biases the disc to in turn bias the lever arms and blades to the low pitch position. The disc is a generally flat planar plate-like member extending radially outwardly from the longitudinal axis at the rear of the hub and includes a preload mechanism accessible at the rear of the hub for adjusting the bias. The disc restricts movement of the lever arms along the guide slots such that the lever arms can move only in unison, which prevents blade flutter. Pivoting of the blades is controlled by both a) movement of the lever arms along the guide slots, and b) arcuate movement of the guide slots as the disc rotates about the longitudinal axis, such that pivoting of each blade from its low pitch position to its high pitch position requires both a) movement of the respective lever arm along its respective guide slot, and b) rotation of the disc to arcuately move the guide slot.
A marine propeller comprising a hub rotatable about a longitudinal axis and having a plurality of blades extending radially outwardly therefrom and pivotable about respective radial pivot axes between a low pitch position and a high pitch position, and a biasing spring coaxial with said longitudinal axis of rotation of said hub and biasing said blades to said low pitch position, wherein said hub has a forward portion mountable to a propeller driveshaft, and a rearward portion, and comprising a preload mechanism at said rearward portion and connected to said blades by a plurality of respective lever arms, wherein said spring is rearward of said radial pivot axes and has a rearward end mounted to said preload mechanism and fixed relative thereto and biasing said blades to said low pitch position, said lever arms having rearward ends slidable along said preload mechanism along a radial direction perpendicular to said longitudinal axis.
A marine propeller comprising a hub rotatable about a longitudinal axis and having a plurality of blades extending radially outwardly therefrom and pivotable about respective radial pivot axes between a low pitch position and a high pitch position, and a biasing spring coaxial with said longitudinal axis of rotation of said hub and biasing said blades to said low pitch position, a plurality of lever arms connected to respective said blades and extending rearwardly within said hub, and a preload mechanism adjustable mounted between said lever arms and said spring to adjust preload bias biasing said blades to said low pitch position, each lever arm having a forward end nonrotatably mounted to a respective said blade at said pivot axis and pivotable therewith such that said blade and said lever arm have the same pivot axis and pivot in unison thereabout.
A marine propeller comprising a hub rotatable about a longitudinal axis and having a plurality of blades extending radially outwardly therefrom and pivotable about respective radial pivot axes between a low pitch position and a high pitch position, said hub comprising a cylindrical sidewall having an inner surface defining the interior of said hub, and an outer surface defining the exterior of said hub, a plurality of trunnions extending radially through said cylindrical sidewall and having outer ends attached to respective said blades, and having inner ends in the interior of said hub, a plurality of lever arms each extending rearwardly in the interior of said hub from a respective said trunnion, each lever arm being movable between a first position corresponding to said low pitch position of its respective said blade, and a second position corresponding to said high pitch position of its respective said blade, a disc having a plurality of guide slots each receiving and retaining a respective said lever arm and restricting movement of said lever arms along said guide slos such that said lever arms can move only in unison between said first and second positions, said lever arms having rearward ends slidable along said disc away from said longitudinal axis, each lever arm having a forward end nonrotatably mounted to a respective said blade at said pivot axis and pivotable therewith such that said blade and said lever arm have the same pivot axis and pivot in unison thereabout.
A marine propeller comprising a hub rotatable about a longitudinal axis and having a plurality of blades extending radially outwardly therefrom and pivotable about respective radial pivot axes between a low position and a high pitch position, said hub comprising a cylindrical sidewall having an inner surface defining the interior of said hub, and an outer surface defining the exterior of said hub, a plurality of trunnions extending radially through said cylindrical sidewall and having outer ends attached to respective said blades, and having inner ends in the interior of said hub, a plurality of lever arms each extending rearwardly in the interior of said hub from a respective said trunnion, each lever arm being movable between a first position corresponding to said low pitch position of its respective said blade, and a second position corresponding to said high pitch position of its respective said blade, wherein said lever arms have centrifugal weights moving outwardly due to centrifugal force with increasing propeller rotational speed, to pivot said blades to said high pitch position, and wherein each said blade has a counteractive hydrodynamic force generating area generating an up-pitching moment about the respective pivot axis which moment increases with decreasing angle of attack to pivot said blade to said high pitch position, said centrifugal force acting in combination with said hydrodynamic force generating said up-pitching moment to pivot said blade to said high pitch position, said lever arms having rearward ends slidable along said preload mechanism outwardly of said longitudinal axis, each lever arm having a forward end nonrotatably mounted to a respective said blade at a respective said trunnion at said pivot axis and pivotable therewith such that said blade and said lever arm have the same pivot axis and pivot in unison thereabout, such that said rearward ends of said lever arms art movable solely in an arc about the respective pivot axis of the respective blade.
Dependencies are inferred from the claim text.