Boat keel stabilizer system for trolling

This invention relates to a fold-able panel as keel stabilizer for small boats of up to 20 feet in length approximately during trolling speeds of up to ten miles per hour approximately, such that the same motor can be used for trolling as well as higher speed point to point travel. More particularly it relates to adding a fold-able panel along the side of the boat closer to the transom. The panel when opened or unfolded extends below the bottom of the boat and provides stabilization during trolling. The fulcrum of the panels is generally above the water-line.

RELATED DOCUMENT 
This invention is based on the concept disclosed and filed under USPTO 
Disclosure Document Program which was assigned document number 353,399 on 
May 2, 1994. 
1. Background 
This invention relates to an improvement in boats. Specifically the 
invention relates to a keel stabilizer for small boats of up to 20 feet in 
length approximately during trolling speeds of up to ten miles per hour 
approximately, such that the same motor can be used for trolling as well 
as higher speed point to point travel. More particularly it relates to 
adding a fold-able panel along the side of the boat closer to the transom. 
The panel when opened or unfolded extends below the bottom of the boat and 
provides stabilization during trolling and resistance to drifting in windy 
conditions. The fulcrum of the panels is generally above the water-line. 
The panel is closed or folded for towing of the boat. While the keel may be 
incorporated into OEM boats, the kit also includes means for easily 
attaching the kit to any boat. In either configuration means are included 
for easily locking the keel panel in open/unfolded and closed/folded 
position without any tools or external instrumentalities. 
2. Prior Art 
A formal preliminary prior art search has not yet been conducted. But the 
inventor is intimately familiar with the prior art. The best know prior 
art is U.S. Pat. No. 4,597,348 granted to Otakar Jonas on Jul. 1, 1986 for 
"Detachable Keel for Small Boats. This device requires detaching the keel 
from the boat during towing and re-attaching for stabilization during 
trolling in water. Following are other tangentially related typical 
examples of the prior art known to the inventor or his attorney arranged 
in the reverse chronological order. 
a) U.S. Pat. No. 4,911,095 awarded to Alex R. Caye on Mar. 27, 1990 for 
"Collapsible Boat with Removable Transom panel." 
b) U.S. Pat. No. 4,776,295 granted to Allen J. Kline on Oct. 11, 1988 for 
"Boat Flaps for Controlling and Steering a Boat Operating and Low Speeds" 
c) U.S. Pat. No. 4,556,009 granted to Alex R. Caye on Dec. 3, 1985 for 
"Boat with Stabilizing Flaps" 
d) U.S. Pat. No. 4,451,989 conferred upon Lawrence F. Leisstiko on Jun. 5, 
1984 for "Boat Keel Tool" 
e) U.S. Pat. No. 3,633,531 granted to Thomas A. Hays on Jan. 11, 1972 for 
"Trolling Device for Boats" 
Unfortunately none of the prior art devices singly or even in combination 
meet all of the objectives established by the inventor for this Add-a-Keel 
Boat stabilizer. 
OBJECTIVES 
1. It is an objective of this invention to provide an improved boat 
incorporating a simple affordable system for stabilizing small boats 
during trolling or windy conditions. 
2. Another objective of this invention is to provide a means for 
incorporating the device into OEM boats. 
3. Another objective of this invention is to provide a means for easily 
incorporating this device into existing boats. 
4. Another objective of this invention is that the device of this invention 
not interfere with normal towing of the boat. 
5. Another objective of this invention is to provide a means for easily 
switching the position of the keel to extend below bottom of boat during 
trolling or whenever in the water and above bottom of boat during towing. 
6. Another objective of this invention is that it be safe stable and 
reliable. 
7. Another objective of this invention is that it be ergonomically 
designed, environmentally friendly and aesthetically integrated. 
8. Another objective of this invention is that it is easily serviceable. 
9. Another objective of this system is that the user cannot accidentally 
destroy or even damage it. 
10. Another objective of this invention is that it provides versatility and 
variety. 
11. Another objective of this invention is that it be long lasting and 
reliable. 
12. Another objective of this invention is that it meet all federal, state, 
local and other private standards and regulations with respect to safety, 
environment, energy consumption, noise etc. etc. 
13. Another objective of this invention is that it obviate waste of any 
type. 
14. Another objective of this invention is that it not interfere with 
normal functions of the boat or the boater. 
15. Another objective of this invention is that it be adaptable for other 
primary and secondary uses without significant modifications. 
16. Another objective of this invention is that it can be adapted for used 
by physically challenged users. 
17. Another objective of this invention is that the keel be self locking in 
both open and closed positions thereby obviating an external lock. 
18. Another objective of this invention is to reduce the effect of wind 
when the boat is lying still on the water. 
Other objectives of this invention reside in its simplicity, elegance of 
design, ease of manufacture, service and use and even aesthetics as will 
become apparent from the following brief description of the drawing and 
detailed description of the best mode embodiment.

DETAILED DESCRIPTION OF THE BEST MODE EMBODIMENT 
As shown in the drawings wherein like numerals represent like parts 
throughout the several views, there is generally disclosed a fold-able 
Add-a Keel stabilizer 20, on a boat 10. An embodiment of this invention 
comprises adding a fold-able panel 40 or a pair of panels 30,40 with a 
fulcrum 70 or equivalent flaps as keel on the side of the boat near the 
transom. The panel 40 is generally larger in area than panel 30. The panel 
40 can be made even longer, larger and heavier by utilizing the existing 
hinge fulcrum 70. The panel 40 when opened or unfolded extends below the 
bottom of the boat 10 and provides stabilization during trolling or in 
windy conditions. 
The fulcrum 70 is below the water line on the boat 10 so as to ensure that 
the lower flap 40 when in the open position extends below the bottom of 
the boat. The water-line on any boat varies according to the weight. The 
upper panel 30 is generally stationary. The lower panel 40 is generally 
fold-able and moveable. In either configuration means are included for 
automatically locking the keel panel in open/unfolded and closed/folded 
position without any tools or external instrumentalities. 
The folding and unfolding is facilitated by a U shaped connecting member 60 
which is interfaced to lower moveable panel at anchor 61 and to fixed 
upper panel at anchor 61' through a hinge-able member 65. 
For safety and ease of use hinge-able member 65 friction or grip fits into 
member 62 in two positions one corresponding to the folded position and 
the other corresponding to the open or extended position of the flaps or 
panels 30,40. This locking position is achieved. 
This is accomplished when the member 65 travels beyond the vertical or 
beyond 180 degrees such that fulcrum 50 is below and beyond fulcrum 51. 
In other words when the fulcrum 50 goes past the imaginary line formed by 
fulcrums 51 and 52, the member 65 locks in either the upper or the lower 
position. It should also be noted that whenever member 65 is down, the 
panel 40 is also down and vice versa. 
The combination of members 62 and 65 facilitates locking of the panels in 
open and closed position automatically thereby obviating the need for an 
external lock. The panel 40 when opened or unfolded extends below the 
bottom of the boat 10 and provides stabilization during trolling and windy 
conditions. 
The panel is closed or folded for towing of the boat. The DIY 
(Do-It-Yourself) kit also includes OEM double sided sticky tape as a means 
for easily attaching the kit to any boat as well as spacers 80 for snug 
interface between the panels 30, 40 and the boat 10. Spacers may be 
modular and circular shaped washers of varying thickness or they may be 
long and tapered to more readily follow contour of the boat. 
In either configuration a OEM or DIY Kit snap fastener, a friction fit 
member or other equivalent means which perform the same function in 
substantially the same manner with substantially the same result of 
securing the panel in open and closed position are included for easily 
locking the keel panel in open/unfolded and closed/folded position without 
any tools or external instrumentalities. 
The fold-able keel in turn comprises a stationary panel 30 and an 
extendable panel 40. The stationery panel 30 is generally smaller in area 
and generally triangular. The moveable panel 40 is generally larger and 
rectangular. 
The stationary panel 30 is affixed to the boat with double sticky 3M OEM 
tape or screws or the like device. The extendible panel has curved edges 
or rounded corners 42 so as to minimize air resistance during towing in 
folded position and to prevent accumulation of pond weeds in the unfolded 
position in the water. 
Hinge 70 connects the two panels 30 and 40 which need not be equal and may 
have an additional fold-able line as fulcrum 70 between the two panel 30 
and 40. Also included is an arm 60 connected to the fold-able panel 40 and 
stationary panel 30 via member lock-able member 65. As shown in FIGS. 7 & 
9, the arm 60 can be anchored at two positions 62 on the boat for flaps in 
open and closed position respectively. 
OPERATION 
The device is easy to install and use. To install merely attach the fixed 
keel panel to the side of the boat near the transom with screws or OEM 
approved 3M Double sided sticky tape provided for the purpose in the kit. 
The arm to the extendible panel, the fasteners respectively to the boat 
and the panels in their natural closed and open positions. 
To use the keel close the panel in the folded position during towing and in 
the open or unfolded position during trolling, windy conditions or when 
lying still in the water. 
To close the keel the user simply holds the U shaped connecting rod 60 as 
if it were a handle and moves it out and up until member 65 self locks in 
the vertical position. 
To open the keel the user merely pulls out the U shaped connecting rod 
member 60 and down into a vertical position till the member 65 self locks 
in the downward position. Again it should be noted that whenever member 65 
is down the panel 40 is also down and vice versa. 
DEFINITIONS 
Great care has been taken to use words with their conventional dictionary 
definitions. Following definitions are included here for clarification. 
Interface=Relationship between two entities. 
DIY=Do It Yourself 
Gunwale=Upper rim of Boat 
(Note: Gunwale is Pronounced Gunnel) 
OEM=Original Equipment Manufacturer 
TRANSOM=A transverse beam fixed across the stern post of a ship. 
The inventor has given a non-limiting description of the concept. Many 
changes may be made to this design without deviating from the spirit of 
the concept of the invention. Examples of such contemplated variations 
include the following. 
a) The keel may be positioned differently on the boat. 
b) The various flaps of the keel may be proportioned and sized differently. 
c) A different opening and closing mechanism may be employed. 
d) A different method of attachment of the keel may be employed. 
e) The device may be adapted for other related angling applications. 
f) A different OEM version may be devised. 
g) shape of the flaps may be changed. 
h) A fold-able single flap or a pair of flaps may be employed. 
i) Folding line fulcrum's position may be changed. 
j) Relationship of water-line to fulcrum or to bottom of the boat may be 
varied. 
k) A different self locking means may be employed. 
l) The spacers may be in the form of modular circular washers of varying 
thickness or in the form of strips of varying thickness to more readily 
conform to the contours of the boat. 
Other changes such as aesthetic and substitution of newer materials as they 
become available which substantially perform the same function in 
substantially the same manner with substantially the same result without 
deviating from the spirit of this invention may be made. 
Following is a listing of the components used in this embodiment arranged 
in ascending order of the reference numerals for ready reference of the 
reader. 
01=Water or Water-line 
10=Boat 
11=Boat Trailer 
12=Transom (AFT) of boat of boat 
15=Bottom of Boat 
20=Keel generally 
30=Fixed Panel or un-fold-able portion thereof 
40=Extendible Keel panel 
42=Curved streamlined corners of extendible panel 
50=Fulcrum between members 60 and 65 
51=Fulcrum between member 65 and anchor 61' on upper stationary panel. 
52=Fulcrum between member 60 and anchor 61 on lower moveable panel. 
60=U shaped Arm or Handle Member 
61=Anchor on lower moveable panel 
61'=Anchor on Upper Stationery Panel 
62=Arm interface to stationary upper panel 
65=A link member between arm 60 and interface 62 
70=Optional fulcrum in panels 
80=Panel boat interface spacers 
While this invention has been described with reference to illustrative 
embodiments, this description is not intended to be construed in a 
limiting sense. Various modifications and combinations of the illustrative 
embodiments as well as other embodiments of the invention will be apparent 
to person skilled in the art upon reference to this description. It is 
therefore contemplated that the appended claims will cover any such 
modifications, embodiments as fall within the true scope of the invention.