US2752874A - Boat stabilizer - Google Patents

Boat stabilizer Download PDF

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US2752874A
US2752874A US368333A US36833353A US2752874A US 2752874 A US2752874 A US 2752874A US 368333 A US368333 A US 368333A US 36833353 A US36833353 A US 36833353A US 2752874 A US2752874 A US 2752874A
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boat
fin
horizontal
water
stabilizer
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Held Ben
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    • BPERFORMING OPERATIONS; TRANSPORTING
    • B63SHIPS OR OTHER WATERBORNE VESSELS; RELATED EQUIPMENT
    • B63BSHIPS OR OTHER WATERBORNE VESSELS; EQUIPMENT FOR SHIPPING 
    • B63B39/00Equipment to decrease pitch, roll, or like unwanted vessel movements; Apparatus for indicating vessel attitude
    • B63B39/06Equipment to decrease pitch, roll, or like unwanted vessel movements; Apparatus for indicating vessel attitude to decrease vessel movements by using foils acting on ambient water
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B63SHIPS OR OTHER WATERBORNE VESSELS; RELATED EQUIPMENT
    • B63BSHIPS OR OTHER WATERBORNE VESSELS; EQUIPMENT FOR SHIPPING 
    • B63B39/00Equipment to decrease pitch, roll, or like unwanted vessel movements; Apparatus for indicating vessel attitude
    • B63B39/06Equipment to decrease pitch, roll, or like unwanted vessel movements; Apparatus for indicating vessel attitude to decrease vessel movements by using foils acting on ambient water
    • B63B2039/067Equipment to decrease pitch, roll, or like unwanted vessel movements; Apparatus for indicating vessel attitude to decrease vessel movements by using foils acting on ambient water effecting motion dampening by means of fixed or movable resistance bodies, e.g. by bilge keels

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  • This invention relates to a boat stabilizer and has for a general object the provision of a device which will damp movements of a boat laterally with respect to its horizontal position upon the water.
  • Another object of the invention is to provide a stabilizing attachment which will minimize side rocking and also minimize pitching of the boat during rapid forward motion.
  • a further object of the invention is to provide fin means in a boat stabilizer which are shiftable to present a width consonant with the forward speed of the boat while furnishing adequate protection against both rocking and pitching.
  • a still further object of the invention is to provide a device of the class described which will be inexpensive and easy to install and operate so as to give to small boats a stability comparable to that characteristic of larger boats.
  • Fig. 1 is a perspective view of a small boat having attached thereto a pair of my boat stabilizers;
  • Fig. 2 is a plan view of a boat stabilizer in extended position and showing its retracted position in dotted line;
  • Fig. 3 is a vertical section of the boat stabilizer taken on the line 33 of Fig. 2.
  • my invention is intended to be used on vessels such as a small conventional rowboat indicated generally at 10.
  • Small rowboats have a tendency to rock much more easily when small influences are exerted laterally to the general longitudinal direction thereof. For example, when a person sitting in the boat shifts his weight or leans forwardly, as when fishing, a small boat will tend to rock in a much more pronounced manner than a large boat. By the same token, during forward movement of the boat waves and movement of the occupants will tend to cause the boat to pitch, and this pitching movement is likewise exaggerated in small boats as opposed to large boats.
  • My invention comprehends a boat stabilizer shown generally at 11, and preferably a pair of such boat stabilizers which may be attached to the side or gunwale 12 of boat at a position intermediate the ends thereof.
  • the boat stabilizer has an upstanding mounting vane 13 which is preferably constructed of thin metallic structure and having an inwardly bent bracket 14 suitable for attachment to the gunwale 12.
  • the upstanding mounting vane 13 forms generally a fiat plane which is disposed in parallel relation with the longitudinal direction of the boat and has its lower end extending downwardly below the surface of the water as shown in Fig. 1.
  • a pivot plate 15 may be formed at the lower end of the vane 13 by bending outwardly a portion 'ice thereof to lie in a horizontal plane and substantially at right angles with respect to the upstanding vane 13.
  • a horizontal fin 17 Pivotally mounted to the upstanding mounting vane medially of its outwardly extending pivot plate 15, as for example on the pivot pin 6, is a horizontal fin 17 which is preferably constructed of a thin sheet of metal material as shown.
  • the horizontal fin 17 may be provided with an abutting stop member 18 and guide brackets 19 and 20 as shown.
  • the horizontal fin presents a flat area having a length greater than the width thereof and is pivotally mounted at 16 adjacent the innermost end thereof.
  • One of the long edges 21 of the horizontal fin consitutes a leading edge when the fin is disposed in its outermost position shown in Fig. 1 and the other long edge 22 of the fin 17 comprises a trailing edge.
  • control means which are securable to the side of the boat, the control means being indicated generally at 25.
  • the journals may comprise offset areas 27 formed directly in the surface of vane 13 and within which the rod 26 may rotate.
  • the upper end of rod 26 may be provided with means for turning the rod such as crank 28 and the lower end of rod 26 has an arm extension 29 which extends through the guide 19 and through the guide bracket 20.
  • Thehorizontal fins are left in their outward position when the boat is moved forwardly at moderate speeds as when rowing or when the boat is propelled by an outboard motor at moderate speeds. If it is desired to bring the boat to a higher rate of speed the leading edge 21 will present a dimension too long for the higher speeds. in other words, the greater leading edge will offer a resistance which will tend to prevent the boat from attaining maximum speeds although the stability thereof will be greatly improved. I have found, however, that by providing for presenting a smaller leading edge as at 23 the frictional resistance will be cut down while maintaining a good stabilizing effect. The higher the rate of speed, the more ditficult it be comes for an occupant to cause sudden oscillation by shifting his weight.
  • the upstanding mounting vane 13 provides additional stabilizing effect at the higher speeds,-thevane slicingthrough the water, yet presenting a considerable area against'lateral shifting movement.
  • a boat stabilizer for attachment to the side of a vessel such as a conventional small rowboat comprising,
  • a thin fin presenting a horizontal area having a length greater than the width thereof and pivotally mounted for lateral swinging movement upon said mounting vane at a lower underwater position thereon, and control means securable to the side of said'boat for swinging the thin horizontal fin between an outward position presenting a water-cutting leading edge having a longer over-all dimension andan inward position presenting a shorter water-cutting leading edge, said area all the while being fully presented to the water above and below whereby to effect a stabilizing influence upon said boat'while minimizing the frictional resistance created by forward movement of the boat.
  • a boat stabilizer for attachment to the. side of a vesselsuch as a conventional small rowhoat comprising, an upstanding mounting vane securable to the side of said boat and extendible downwardly into the water, a horizontal fin having a generally elongated and rectangular shape pivotally mounted adjacent one end thereof to a lower underwater position on said mounting vane and swingable from an outward lateral relation to the side of said boat to a second outward position more closely adjacent the side. of said boat, and control means securable to the side of said boat for effecting the swinging movement of said horizontal fin to create a stabilizinginfluence upon said boat with the full area thereof presented to the water above and below at'hoth positions while. minimizing the frictional resistance created by forward movement of the boat'in the second of said positions.
  • a boat stabilizerfor attachment to the side'of a vessel such as a conventional small rowboat comprising, an upstanding mounting vane securable to the side of said boat and extendible downwardly into the water, a horizontal fin presenting a flat area having a length greater than the width thereof and pivotally mounted adjacent one end thereof for horizontal swinging movement to said mounting vane at a lower underwater position thereon, and a control rod journaled on said mounting vane and having a radial arm extending outwardly therefrom in abutting relation with said fin for reciproeating the horizontal 'fin between a position presenting a water-cutting leading edge having a longer over-all dimension and a position presenting a shorter water-cutting leading edge said fiat area remaining in full contact with the water above and below whereby to effect selective stabilizing influence upon said boat at both low and high speeds.
  • a boat stabilizer for attachment to the side of a vessel such as a conventional small rowboat comprising, an upstanding mounting vane securable to the side of said boat and extendible downwardly into the water, a horizontal fin presenting a tilt area having a length greater than the width thereof and pivotally mounted for horizontal swinging movement to said mounting vane at a lower underwater position thereon, said horizontal fin in its most outward position presenting a leading down-turned edge and a trailing up-turned edge whereby said horizontal fin may be shifted from its most outwardiy extending position to a lesser outwardly extending position said down-turned and up-turned edges tending to settle and stabilize the boat during moderate forward speeds thereof and the fin in its less extended. position stabilizing. said boat while minimizing frictional resistance during higher speeds of the boat.
  • a boat stabilizer for attachment to the. side of a vessel such as a conventional small rowboat comprising, mounting means securable to the side of a boat and extendible rigidly downward into the water, a flat and thin fin having a horizontal area of a greater length than width and pivotally mounted for horizontal swinging movement upon said mounting means at a lower underwater position, and control means mountable at the side of said boat and having an upper extension for manual actuation and a lower extension in engagement'with said fin for swinging the fin horizontally between a position presenting a leading edge of the greater length of the horizontal fin in water-cutting fashion and a position presenting a leading edge of the shorter width, said fin all the while maintaining said horizontal area in full contact with the water above and below whereby to effect a stabilizing influence upon the boat while providing a lesser frictional resistance during greater speeds in the forward movement of the boat.

Description

B. HELD BOAT STABILIZER July 3, 1956 Filed July 16, 1955 iinited States Patent 6 BOAT STABILIZER Ben Held, Bemidji, Minn.
Application July 16, 1953, Serial N0. 368,333
Claims. (Cl. 114-426) This invention relates to a boat stabilizer and has for a general object the provision of a device which will damp movements of a boat laterally with respect to its horizontal position upon the water.
Another object of the invention is to provide a stabilizing attachment which will minimize side rocking and also minimize pitching of the boat during rapid forward motion.
A further object of the invention is to provide fin means in a boat stabilizer which are shiftable to present a width consonant with the forward speed of the boat while furnishing adequate protection against both rocking and pitching.
A still further object of the invention is to provide a device of the class described which will be inexpensive and easy to install and operate so as to give to small boats a stability comparable to that characteristic of larger boats.
These and other objects and advantages of my invention will more fully appear from the following description made in connection with the accompanying drawings wherein like reference characters refer to similar parts throughout the several views and in which:
Fig. 1 is a perspective view of a small boat having attached thereto a pair of my boat stabilizers;
Fig. 2 is a plan view of a boat stabilizer in extended position and showing its retracted position in dotted line; and
Fig. 3 is a vertical section of the boat stabilizer taken on the line 33 of Fig. 2.
Referring now more particularly to the drawing, my invention is intended to be used on vessels such as a small conventional rowboat indicated generally at 10. Small rowboats have a tendency to rock much more easily when small influences are exerted laterally to the general longitudinal direction thereof. For example, when a person sitting in the boat shifts his weight or leans forwardly, as when fishing, a small boat will tend to rock in a much more pronounced manner than a large boat. By the same token, during forward movement of the boat waves and movement of the occupants will tend to cause the boat to pitch, and this pitching movement is likewise exaggerated in small boats as opposed to large boats.
My invention comprehends a boat stabilizer shown generally at 11, and preferably a pair of such boat stabilizers which may be attached to the side or gunwale 12 of boat at a position intermediate the ends thereof. The boat stabilizer has an upstanding mounting vane 13 which is preferably constructed of thin metallic structure and having an inwardly bent bracket 14 suitable for attachment to the gunwale 12. The upstanding mounting vane 13 forms generally a fiat plane which is disposed in parallel relation with the longitudinal direction of the boat and has its lower end extending downwardly below the surface of the water as shown in Fig. 1. A pivot plate 15 may be formed at the lower end of the vane 13 by bending outwardly a portion 'ice thereof to lie in a horizontal plane and substantially at right angles with respect to the upstanding vane 13.
Pivotally mounted to the upstanding mounting vane medially of its outwardly extending pivot plate 15, as for example on the pivot pin 6, is a horizontal fin 17 which is preferably constructed of a thin sheet of metal material as shown. The horizontal fin 17 may be provided with an abutting stop member 18 and guide brackets 19 and 20 as shown. The horizontal fin presents a flat area having a length greater than the width thereof and is pivotally mounted at 16 adjacent the innermost end thereof. One of the long edges 21 of the horizontal fin consitutes a leading edge when the fin is disposed in its outermost position shown in Fig. 1 and the other long edge 22 of the fin 17 comprises a trailing edge. For additional stability, I prefer to have the leading edge 21 downturned slightly and the trailing edge upturned to a slight degree. On moderate forward speeds of boat 10 this will tend to settle the boat at each side thereof and assist in stabilizing the boat in the water.
When the horizontal fin 17 is swung from its outermost position shown in Fig. 1 to the dotted line position as shown in Fig. 2, the leading edge 21 will lie closely adjacent the side of the boat 10 and the shorter outward end 23 then becomes the leading edge in the forward travel of boat 11]. By the same token the short edge 24 becomes the trailing edge. Since the boat is intended to be used at high speeds with the stabilizer fin in the inward position, I find that it is not necessary to up-turn or down-turn the edges to effect a stabilizing influence during such rapid forward speed of the boat.
In order to effect the swinging movement of one po sition to the other in my boat stabilizer, I employ control means which are securable to the side of the boat, the control means being indicated generally at 25. I prefer to use a rotatable rod 26 which is journaled to the mounting vane in an upstanding position as shown in Fig. l. The journals may comprise offset areas 27 formed directly in the surface of vane 13 and within which the rod 26 may rotate. The upper end of rod 26 may be provided with means for turning the rod such as crank 28 and the lower end of rod 26 has an arm extension 29 which extends through the guide 19 and through the guide bracket 20.
In the use and operation of my boat stabilizer, I secure the mounting vane 13 to the side of the boat in a convenient position with the horizontal fin projecting in its outermost position as shown in Fig. l. A second boat stabilizer is placed at the opposite side of boat 10 in reverse and counteracting relation. When the boat 10 is standing still in the water, the horizontal fins 17 at each side of the boat will exert a damping effect upon the sideway oscillation of the boat and thus prevent pronounced movement thereof when occupants shift their weight within the boat. The upstanding mounting vanes 13 also present flat surfaces within water which will tend to assist in preventing sudden lateral shifting of the entire boat 10 as where the wind is blowing upon one side of the boat. Thehorizontal fins are left in their outward position when the boat is moved forwardly at moderate speeds as when rowing or when the boat is propelled by an outboard motor at moderate speeds. If it is desired to bring the boat to a higher rate of speed the leading edge 21 will present a dimension too long for the higher speeds. in other words, the greater leading edge will offer a resistance which will tend to prevent the boat from attaining maximum speeds although the stability thereof will be greatly improved. I have found, however, that by providing for presenting a smaller leading edge as at 23 the frictional resistance will be cut down while maintaining a good stabilizing effect. The higher the rate of speed, the more ditficult it be comes for an occupant to cause sudden oscillation by shifting his weight.
It is also to be noted that the upstanding mounting vane 13 provides additional stabilizing effect at the higher speeds,-thevane slicingthrough the water, yet presenting a considerable area against'lateral shifting movement.
Itwill, of course, be understood that various changes may be made in the form, details, arrangement and proportions of the parts without departing from the scope of myinvention.
' What I claimis:
1. A boat stabilizer for attachment to the side of a vessel such as a conventional small rowboat comprising,
anupstanding thin mounting vane securable to the side.
of said boat and lying in a plane disposed substantially parallel tothe longitudinal direction of the boat with the lower portion thereof extendible downwardly into the water, a thin fin presenting a horizontal area having a length greater than the width thereof and pivotally mounted for lateral swinging movement upon said mounting vane at a lower underwater position thereon, and control means securable to the side of said'boat for swinging the thin horizontal fin between an outward position presenting a water-cutting leading edge having a longer over-all dimension andan inward position presenting a shorter water-cutting leading edge, said area all the while being fully presented to the water above and below whereby to effect a stabilizing influence upon said boat'while minimizing the frictional resistance created by forward movement of the boat.
2. A boat stabilizer for attachment to the. side of a vesselsuch as a conventional small rowhoat comprising, an upstanding mounting vane securable to the side of said boat and extendible downwardly into the water,a horizontal fin having a generally elongated and rectangular shape pivotally mounted adjacent one end thereof to a lower underwater position on said mounting vane and swingable from an outward lateral relation to the side of said boat to a second outward position more closely adjacent the side. of said boat, and control means securable to the side of said boat for effecting the swinging movement of said horizontal fin to create a stabilizinginfluence upon said boat with the full area thereof presented to the water above and below at'hoth positions while. minimizing the frictional resistance created by forward movement of the boat'in the second of said positions.
3. A boat stabilizerfor attachment to the side'of a vessel such as a conventional small rowboat comprising, an upstanding mounting vane securable to the side of said boat and extendible downwardly into the water, a horizontal fin presenting a flat area having a length greater than the width thereof and pivotally mounted adjacent one end thereof for horizontal swinging movement to said mounting vane at a lower underwater position thereon, and a control rod journaled on said mounting vane and having a radial arm extending outwardly therefrom in abutting relation with said fin for reciproeating the horizontal 'fin between a position presenting a water-cutting leading edge having a longer over-all dimension and a position presenting a shorter water-cutting leading edge said fiat area remaining in full contact with the water above and below whereby to effect selective stabilizing influence upon said boat at both low and high speeds.
4. A boat stabilizer for attachment to the side of a vessel such as a conventional small rowboat comprising, an upstanding mounting vane securable to the side of said boat and extendible downwardly into the water, a horizontal fin presenting a tilt area having a length greater than the width thereof and pivotally mounted for horizontal swinging movement to said mounting vane at a lower underwater position thereon, said horizontal fin in its most outward position presenting a leading down-turned edge and a trailing up-turned edge whereby said horizontal fin may be shifted from its most outwardiy extending position to a lesser outwardly extending position said down-turned and up-turned edges tending to settle and stabilize the boat during moderate forward speeds thereof and the fin in its less extended. position stabilizing. said boat while minimizing frictional resistance during higher speeds of the boat.
5. A boat stabilizer for attachment to the. side of a vessel such as a conventional small rowboat comprising, mounting means securable to the side of a boat and extendible rigidly downward into the water, a flat and thin fin having a horizontal area of a greater length than width and pivotally mounted for horizontal swinging movement upon said mounting means at a lower underwater position, and control means mountable at the side of said boat and having an upper extension for manual actuation and a lower extension in engagement'with said fin for swinging the fin horizontally between a position presenting a leading edge of the greater length of the horizontal fin in water-cutting fashion and a position presenting a leading edge of the shorter width, said fin all the while maintaining said horizontal area in full contact with the water above and below whereby to effect a stabilizing influence upon the boat while providing a lesser frictional resistance during greater speeds in the forward movement of the boat.
References Citedin the file of this patent UNITED STATES PATENTS 336,365 Welch Feb. 16, 1886 739,734 Spear Sept. 22, 1903 1,136,306 Beck Apr. 20, 1915 1,809,675 Chison June 9, 1931 2,596,194 Anderson May 13, 1952 FOREIGN PATENTS 100,275 Austria June 25, 1925
US368333A 1953-07-16 1953-07-16 Boat stabilizer Expired - Lifetime US2752874A (en)

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Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4182255A (en) * 1978-02-22 1980-01-08 Reid Bruce D Below waterline deployable hull stabilizing members
US4846743A (en) * 1987-11-06 1989-07-11 Ping Chuan Chang Water skiing buoyant shoes
US5819678A (en) * 1996-04-29 1998-10-13 Austin; Vincent P. Boat keel stabilizer system for trolling
EP1170204A1 (en) * 2000-05-16 2002-01-09 Mitsubishi Heavy Industries, Ltd. Motion reduction apparatus and floating body therewith
US6408780B1 (en) * 1998-10-30 2002-06-25 Mitsubishi Heavy Ind Ltd Wave-resistant mega-float
US8485115B2 (en) 2010-09-30 2013-07-16 Bombardier Recreational Products Inc. Watercraft with bow sponsons

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US336365A (en) * 1886-02-16 Center-board for vessels
US739734A (en) * 1902-12-17 1903-09-22 Electric Boat Co Submarine boat.
US1136306A (en) * 1914-09-11 1915-04-20 Joseph Beck Outrigger for boats.
AT100275B (en) * 1924-04-14 1925-06-25 Adolf Ing Werthner External leeboard for boats.
US1809675A (en) * 1929-07-06 1931-06-09 Chison John Safety device for boats
US2596194A (en) * 1949-01-05 1952-05-13 E C Wegert Boat outrigger float

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US336365A (en) * 1886-02-16 Center-board for vessels
US739734A (en) * 1902-12-17 1903-09-22 Electric Boat Co Submarine boat.
US1136306A (en) * 1914-09-11 1915-04-20 Joseph Beck Outrigger for boats.
AT100275B (en) * 1924-04-14 1925-06-25 Adolf Ing Werthner External leeboard for boats.
US1809675A (en) * 1929-07-06 1931-06-09 Chison John Safety device for boats
US2596194A (en) * 1949-01-05 1952-05-13 E C Wegert Boat outrigger float

Cited By (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4182255A (en) * 1978-02-22 1980-01-08 Reid Bruce D Below waterline deployable hull stabilizing members
US4846743A (en) * 1987-11-06 1989-07-11 Ping Chuan Chang Water skiing buoyant shoes
US5819678A (en) * 1996-04-29 1998-10-13 Austin; Vincent P. Boat keel stabilizer system for trolling
US6408780B1 (en) * 1998-10-30 2002-06-25 Mitsubishi Heavy Ind Ltd Wave-resistant mega-float
EP1170204A1 (en) * 2000-05-16 2002-01-09 Mitsubishi Heavy Industries, Ltd. Motion reduction apparatus and floating body therewith
US6652193B2 (en) 2000-05-16 2003-11-25 Mitsubishi Heavy Industries, Ltd. Swaying reduction apparatus and floating body therewith
US20040071498A1 (en) * 2000-05-16 2004-04-15 Mitsubishi Heavy Industries Ltd. Motion reduction apparatus and floating body therewith
US7677838B2 (en) 2000-05-16 2010-03-16 Mitsubishi Heavy Industries, Ltd. Motion reduction apparatus and floating body therewith
US8485115B2 (en) 2010-09-30 2013-07-16 Bombardier Recreational Products Inc. Watercraft with bow sponsons

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