Transmission for dual propellers driven by an inboard marine engine
OwnerStefan Verneainventor
Life of this patent
Estimating the term…
Abstract
Transmission for a single engine drive for dual concentric propellers in a straight or V-drive arrangement with the straight-drive including four shafts and nine gears and the V-drive adding two more shafts and four more gears.
Claims6
A transmission for an inboard marine engine driving dual, counter-rotating, closely spaced concentric propellers in a small recreational boat, comprising an inner drive shaft rotating concentrically inside an outer hollow drive shaft, said drive shafts connected respectively to an inner propeller and an outer propeller, and connected to each other through a plurality of gears, said drive shafts having respectively proximal forward ends adjacent said engine and distal aft ends adjacent said propellers;
- said engine driving said inner shaft on which are mounted an assembly of a forward drive gear, a clutch, and a rearward drive gear with said clutch adapted to selectively release either of said drive gears from engagement with said inner drive shaft while operatively engaging the other of said drive gears to said inner drive shaft;
- said plurality of gears being mounted on said inner drive shaft, a first auxiliary shaft, and a second auxiliary shaft;
- said inner drive shaft having rigidly mounted thereon a forward inner dirve shaft gear adjacent said assembly and a forward outer drive shaft gear aft of said inner drive shaft gear;
- and freely rotatable about said inner drive shaft, said first auxiliary shaft having rigidly mounted thereon a forward first gear meshed with one of the drive gears of said assembly, a middle second gear, and an aft third gear meshed with said outer shaft drive gear;
- said second auxiliary shaft having rigidly mounted thereon a forward first gear meshed with the other of the dirve gears of said assembly and also meshed with said middle second gear, and an aft second gear meshed with said inner shaft dirve gear;
- and connecting means coupling said inner shaft drive gear to said inner propeller and coupling said outer shaft drive gear to said outer propeller.
A V-drive transmission connected to an inboard marine engine for driving dual counter-rotating closely spaced concentric propellers on a small recreational boat comprising an inner drive shaft rotating concentrically inside an outer hollow drive shaft, said drive shafts rotating in opposite directions with respect to each other;
- an inner propeller rigidly mounted on said inner drive shaft and an outer propeller rigidly mounted on said outer drive shaft, said drive shafts extending from said engine to said propellers along two intersecting straight-line legs, forming a V-shape, one said leg being a main drive shaft, which is substantially horizontal and the other said leg being a branch drive shaft, which is directed downwardly at an acute angle to terminate at said propellers underwater outside the hull of the boat;
- said transmission comprising a first combination of a main inner drive shaft rotatable inside a main outer drive shaft, said first combination extending from a forward position adjacent said engine to a rearward knee joint, a second combination of a branch inner drive shaft rotatable inside a branch outer dirve shaft, said second combination extending from said knee joint to said propellers, and a plurality of gears, each attached to one of the said shafts of said first and second combinations;
- said first combination including said main inner drive shaft, said main outer drive shaft, a first auxiliary shaft and a second auxiliary shaft and eleven gears mounted on one of said shafts of said first combination, said main inner drive shaft having mounted thereon in the order listed from adjacent said engine to adjacent said knee joint, a forward driving gear, a clutch, a rearward driving gear, a forward inner drive gear, and an aft inner drive gear, said first auxiliary shaft having rigidly mounted thereon three spaced gears in the order listed below from adjacent said engine to adjacent said knee joint, a forward first gear meshed with said forward driving gear, a middle second gear, and an aft third gear;
- said second auxiliary shaft having rigidly mounted thereon two spaced gears in the order listed below from adjacent said engine to adjacent said knee joint, a forward first gear meshed with both said rearward driving gear and said middle second gear, and an aft second gear meshed with said forward inner drive gear;
- said main outer drive shaft having rigidly mounted thereon a forward first gear meshed with said aft third gear on said first auxiliary shaft and an aft second gear at the aft end of said main outer drive shaft at said knee joint;
- said second combination including said branch inner drive shaft with an aft gear rigidly mounted thereon at said knee joint and meshed with said aft second gear of said main inner drive shaft, and an outer drive gear rigidly mounted on said branch outer drive adjacent said knee and meshed with said aft second gear and said main outer drive shaft;
- said inner and outer propellers being rigidly mounted on the underwater ends respectively of said branch inner drive shaft and said branch outer drive shaft.
Dependencies are inferred from the claim text.