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Publication numberUS1639675 A
Publication typeGrant
Publication dateAug 23, 1927
Filing dateAug 28, 1924
Priority dateAug 28, 1924
Publication numberUS 1639675 A, US 1639675A, US-A-1639675, US1639675 A, US1639675A
InventorsSnadecki William J
Original AssigneeRichard Crane
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Rudder for boats
US 1639675 A
Abstract  available in
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Claims  available in
Description  (OCR text may contain errors)

Aug- 3". w. J. sNADECkl RUDDER FOR BOATS Filed Aim. 28. 1924 Alum I 1mm!!! 9 awuauto'c 7 William J- Snadeckl. 951M emm Patented Aug. 23, 1927.




Application filed August 28, 1924. Serial No. 734,696.

My invention relates to improvements in means for correcting the whirling motion of the water set up by the revolving of a marine propeller, and more particularly has reference to vanes, plates, or planes aft of the propeller against which the whirling water strikes and by which it is more or less straightened out. Due to the pitch of the blades of a propeller the water set inmotion thereby naturally whirls in corkscrewlike fashion creating considerable disturbance proportionate to the energy applied, and considerable percentage of which is wasted due to the fact that it is expended more or less laterally instead of directly astern.

One of the principal objects of my invention is to correct or minimize as much as possible this lateral disturbance of the water so as to thereby increase the thrust or bite of the propeller and its efiective forward effort against the water.

In the accompanying drawings, I have illustrated in Fig. 1, the stern of a boat with vanes or blades upon the rudder, thus embodying an application of my invention. Fig. 2 is a side elevation of a suitable form of rudder showing the application of two vanes preferably curved. Fig. 3 is a similar view showing an arrangement of three vanes, and Fig. & is a plan View looking down upon the rudder.

5 is the hull of the boat, 6 the propeller thereof, 7 the rudder, and 8 the rudder post. 9, 10 indicate two vanes or planes, one on each side of the rudder. These are preferahlv curved as shown and follow immediately in the wake of the propeller. These vanes ride against and upon the disturbed water, tending to iron out or smooth the same, thereby reducing the disturbance and keeping the water more solidly behind the working surfaces of the propeller. In Figs. 2 and 3, I have shown two and three vanes respectively, and of course it will be readily under stood that any number of vanes may be employed and may be positioned and formed in various ways as may be found desirable. In small boat construction, these vanes and planes also serve as a planing surface which becomes more and more effective as the bow lifts when under speed. By this method of smoothing out the lateral agitation of the water, the efiort of the screw is more eifective and works against a denser medium, thereby increasing the speed with a given output of energy. The blades also tend to have a steadying effect and tend to minimize the rocking of the boat on its transverse axis.

Of course it will be understood that various modifications may be made in the construction and arrangement of parts without departing from the spirit of the invention as claimed.

I claim In combination with the rudder of a selfpropelled vessel, vertically spaced vanes projecting laterally from both faces thereof, said vanes curved about a transverse axis.

In testimony whereof I hereunto affix my signature.


Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US3817202 *Jul 5, 1973Jun 18, 1974Outboard Marine CorpAnti-ventilation fence for a trim tab
US4653418 *Jul 1, 1985Mar 31, 1987Ishikawajima-Harima Jukogyo Kabushiki KaishaRudder with wings and method for manufacture thereof
US4825795 *Mar 19, 1987May 2, 1989Slemmons Arthur JSailing craft keel and rudder flow modifiers
US5365870 *Aug 21, 1992Nov 22, 1994Blohm & Voss AgBody equipped with a streamlined profile, in particular a stabilizer fin for ships with a turbulence reducing structure and method of using the turbulence reducing structure
WO2004002818A1 *Jul 9, 2002Jan 8, 2004Ryszard SerugaMulti-face rudder stabilizing device of floating units
U.S. Classification114/167, 114/162
International ClassificationB63H25/38, B63H25/06
Cooperative ClassificationB63H25/38
European ClassificationB63H25/38