US3584590A

US3584590A - Catamaran power boat

Info

Publication number: US3584590A
Application number: US847268A
Authority: US
Inventors: Paul A Rings; Robert P Kauffman Jr; Edward F Kroll
Original assignee: SKIPPER NAUTICAL CORP
Current assignee: SKIPPER NAUTICAL CORP
Priority date: 1969-08-04
Filing date: 1969-08-04
Publication date: 1971-06-15
Anticipated expiration: 1988-06-15

Abstract

A catamaran power boat has two spaced apart hulls interconnected by a substantially flat deck. Straddle-type pedestal seating is provided along the fore and aft center line of the deck with a handlebar-type steering mechanism located at the forward portion of the seating facility. Each hull has a substantially vertical step located approximately one-third of the distance from the aft portion of same. Hydraulic controls operate trim tabs to help the vessel regain a planing attitude during the various stages of the operation thereof.

Description

U n ite States Patent Paul A. Rings Kansas City;

Robert P. Kaufiman, J r.; Edward F. Kroil, both of Grandview, all of, Mo.

Aug. 4, 1969 June 1 5 197 l Skipper Nautical Corporation Grandview, Mo.

Inventors Appl. No. Filed Patented Assignee CATAMARAN POWER BOAT 10 Claims, 10 Drawing Figs.

U.S. Cl 114/665,

114/61, 115/70 Int. Cl 1363b 1/22 Field of Search 114/665 P,

[56] References Cited UNITEQ STATES PATENTS 3,294,055 12/1966 McGuire 115/70 3,373,715 3/1968 Stacey 1. [15/70 Primary Examiner-Andrew H. Farrell Attorney-Sc0field, Kokjer, Scofield and Lowe ABSTRACT: A catamaran power boat has two spaced apart hulls interconnected by a substantially flat deck. straddle-type pedestal seating is provided along the fore and aft center line of the deck with a handlebar-type steering mechanism located at the forward portion of the seating facility.

Each hull has a substantially vertical step located approximately one-third of the distance from the aft portion of same. Hydraulic controls operate trim tabs to help the vessel regain a planing attitude during the various stages of the operation thereof.

PATENTEDJUNISIHYI 3,584,590

SHEET 1 OF 2 INVENTOR 441% A RNEYS CATAMARAN POWER BOAT BRIEF DESCRIPTION OF THE INVENTION The basic catamaran structure has long been recognized as being synonymous with sail boat stability. For example, monohull crafts have utilized an outrigger concept to provide stability without significantly decreasing the mobility of the vessel utilizing same. Our invention makes use of the heretofore known advantages of the catamaran, yet, includes several improvements which are effectively combined to result in a highly efficient, low priced, safe, sturdy, durable and easily transportable power boat having all of the advantages of the catamaran concept.

With the tremendous increase in popularity in power boating and water skiing, a need was quickly established for a safe, maneuverable and inexpensive craft which was capable of towing a number of skiers and comfortably and conveniently accommodating a number of passengers and related gear, yet be operable with a minimum ofpower source.

Our catamaran power boat has two spaced apart parallel hulls which are integrally formed or connected with a substantially flat deck at the upper end extremities thereof. Each hull has a substantially vertical step formed therein at a location which is approximately one-third of the overall length from the aft portion of the boat. A keel plate is located at each hull step to add stability in making turns and to maintain a steady course with minimum drift. I

The upper portion of the deck has straddle pedestal-type seating facilities with a rear swivel seat for skier monitoring. Handlebar-type steering means are located on the forward portion of the seating facility with the operating console in easy reach of the operator. The rear portion of the deck includes a motor well which will accommodate the motor as it is tilted forward and/or associated with fuel lines and tanks.

The underside of our catamaran power boat includes the above-mentioned two parallel hulls with the keel portion occupying the area described by the longitudinal center line of each hull. A motor fairing is located immediately forward of the motor position and protects the motor from the normal turbulence created by the boat moving through the water at high speeds.

Finally, the boat is equipped with a unique steering mechanism and fold-out ladder facility, both of which significantly increase the usability of our boat.

It is an object of our invention to provide a uniquely constructed power boat that is safe, extremely stable at high speeds, and which is convenient for the operator and passengers alike.

Another object of the invention is to provide a power boat of the character described which includes a means for causing the boat to assume the proper planing attitude in an optimum time period while pulling skiers up out of the water. It is an important feature of our invention that the total resistance to boat propulsion is reduced by the hull construction and assisted by the causing means described above.

Another object of the invention is to provide a catamaran power boat having uniquely constructed parallel hulls. It is a feature of our invention that the hulls include a vertical step with a keel plate located thereat to prevent slipping while making turns and maintaining a steady course with minimum drift. We have further found that the vertical step in each hull at approximately one-third the distance from the aft portion of the boat provides for optimum planing of the boat during operation.

A further object of the inventionis to provide a catamaran power boat that includes a motor fairing located on the underside of the motor well portion of same and which operates to break up water turbulence and to protect the motor during normal and high-speed operations thereof.

A still further object of the invention is to provide trim tabs on a powered catamaran with hydraulic controls, therefore, it is a feature of the invention that the trim tabs have three operative positions and is totally controlled by a foot pedal and hydraulic circuit to optimally utilize the hull construction.

Another object of the invention is to provide a unique steering mechanism for a powered catamaran boat. Our steering mechanism incorporates the use of handlebars and has a bellcrank linkage associated therewith so that full rudder control may be had in a relatively short handlebar turning radius.

Another object of the invention is to provide a uniquely constructed permanently attachable foldable boarding ladder for use with powered ski boats and the like.

Other and further objects of the invention, together with the features of novelty appurtenant thereto, will appear in the course of the following description.

DETAILED DESCRIPTION OF THE INVENTION In the accompanying drawings, which form a part of the specification, and are to be read in conjunction therewith, and in which like reference numerals indicate like parts in the various views:

FIG. 1 is a top plan view of a catamaran power boat embodying the invention;

FIG 2 is a bottom plan view of same;

FIG. 3 is a side elevational view of same;

FIG. 4 is a front elevational view of same;

FIG. 5 is a rear elevational view of same;

FIG. 6 is a schematic diagram showing the hydraulic circuit used to operate the associated trim tabs;

FIG. 7 is an enlarged rear elevation view taken generally along the line 7-7 of FIG. 3 in the direction of the arrows and showing the boarding ladder located at the left rear external portion of the catamaran power boat;

FIG. 8 is a sectional view taken along the line 88 of FIG. 5 in the direction of the arrows with the broken line portion used to show the ladder in its folded-down position;

FIG. 9 is an enlarged sectional view taken generally along the line 99 of FIG. 5 in the direction of the arrow and showing motor fairing in elevation; and

FIG. 10 is a diagrammatic view of the steering linkage utilized in the catamaran power boat.

Turning now more particularly to the drawings illustrating the powered catamaran, FIGS. 1 through 5 show the basic structure utilized in our device. As seen therein, the catamaran has two identically shaped parallel hulls I0 and 11 which are interconnected by a substantially flat deck 12. Deck 12 extends from its forward end 12a toward the aft portion of the boat (transom I22) and has a dished-out motor well which is generally represented by the numeral 12b.

Each of the hulls I0 and II has a keel line running longitudinally the length thereof. As shown in FIGS. 2 and 3, there is a substantially vertical step 13 located in each hull. This step 13 occupies a position which is approximately one-third of the entire length of the hull from the aft portion of same. The forward portion of each hull from step 13 is more sharply angled away from the keel line to the vertical sides of same, than is the rear approximately one-third of each hull. To better facilitate forward movement through the water, each hull is contoured at its forward end extremity to present a reduced area, gradually enlarging surface relative to the direction of movement of the boat. A keel plate 14 is attached to the step area of each hull be means ofa bracket 14a which is bolted or otherwise conventionally affixed to each hull at the abovementioned area. The keel plate extends both forwardly of the step and rearwardly thereof so that inadvertent sliding of the craft during sharp turns or drifting is obviated. In this manner the entire craft is stabilized during operation.

Continuing on with the discussion of the under side of the boat, motor well 12b is contoured upwardly in a gradual arc from transom 12c to integrally connect with the under surface of deck 12. The lower surface of well 12b has motor fairing l5 fixedly connected thereto and positioned directly forward of the motors (M) propeller P which operatively propells the boat. The motor fairing is somewhat wedge-shaped (see FIGS.

2 and 3) with the vertex forward so that the water and associated turbulence due to the movement of the boat is forced away from the motor's shaft housing. In this manner, the shaft housing flows relatively smooth through the water without the normal drag thereon which would otherwise be directed to the motor shaft and propeller.

Turning now to the upper side of deck 12, a straddle pedestal-type seating structure is substantially centered on the fore-aft center line of the deck and has approximately four seats thereon. (The seating capacity could be either increased or decrease depending upon the size of the boat and the need for a certain number of available seats.) The forward portion of the straddle pedestal seat construction (hereinafter identified by the numeral 16) contains an operators console 160 with motorcycle-type handlebars 17 extending upwardly therefrom and positioned for optimum control by the person operating the boat and sitting in the forwardmost seat. The rear seat on the seating pedestal 16b may be swivel mounted so that same may be rotated for the purpose of observing water skiers which are being towed by the boat. Finally, the entire mounting pedestal structure 16 may be hollow in nature with a hinged upper seat cushion portion so that the pedestal structure will serve as a storage facility.

Remotely controllable recessed lights 18 are located near the forward portion of the deck as shown in FIGS. l and 3 and are conveniently operated so that they may be either drawn within deck 12 so as to disappear completely or hingedly swung upwardly (see FIG. 3) so that each light directs an illuminating beam above and forwardly of the boat.

The hulls rearward surfaces adjacent transom 120 have trim tabs 19 mounted thereon. As clearly seen in FIGS. and 6, each hull l0 and 1 1 has a separate but mutually controllable trim tab hingedly connected thereon slightly above the lower surface of same. Each of the trim tabs 19 has a hydraulic cylinder 20 associated therewith which includes the conventional extendable piston 20a. Piston 20a is interconnected with its associated tab at its clevised end 20b by pivotally engaging a suitable upturned bracket thereon. Each hydraulic cylinder may be suitably affixed to the transom 12c of the boat by any suitable conventional bracket means.

The hydraulic circuit depicted in FIG. 6 may be utilized to position both trim tabs at the desired location. For instance, the foot pedal 21 is mechanically linked to a reservoir piston 22, same being reciprocally movable within the hydraulic reservoir 23. A single depression of foot pedal 21 results in a high pressure through check valve 24 and through line 24a to each hydraulic cylinder 20. This high pressure condition extends pistons 20a so that the trim tabs 19 are moved to position 19a (see FIG. 6). The tabs will stay in this position 19a until the pedal is pumped again. Another rapid depression of the foot pedal 21 moves the trim tabs down to position 1% and a final pumping of pedal 21 will move the tabs to the position of 19c in a manner similar to that described above with a reference to position 19a. When the operator removes his foot from pedal 21, the normal resistance to the forward movement of the boat will move the trim tabs back to their horizontal positions (shown in solid lines in FIG. 6) with the oil flow being regulated through the valve 25 via line 25a. As suggested above, it is contemplated that the pedal 21b is springbiased in any conventional manner so as to assist in the movement of piston 22 to its upper position when the pedal is not being manually depressed. This condition permits the equalizing oil flow through valve 25 back to reservoir 23.

With the trim tabs so conveniently controllable in the manner described above, the proper planing attitude of the boat is quickly obtainable when pulling water skiers up out of the water into a skiing position. For example, with a number of skiers in the water awaiting to be towed, the boat motor M is usually idling. In this condition, the aft portion of the hulls are also in the water. To achieve maximum efficiency of motor M with our boat, when the throttle is opened and the forward gear engaged, it is necessary that the forward movement of the boat be accomplished with only the hull portions forward of step 13 in contact with the water. By lowering the tabs 19 to a water contacting position (either 19a, 1917 or the boat is forced onto the forward hull portions thereby reducing the skin frictioned resistance to boat propulsion. Since there are three different trim tab water contacting positions, the boat operator may select the appropriate position depending on the towed load (e.g. the water skiers) thereby obtaining the optimum boat planing attitude with a minimum power and time requirement. Furthermore, once the boat attitude has been obtained, the air flow between the hulls (with its associated airfoil effect) and the hull shape cause the frictional drag of the water on the hulls to be reduced so that high speeds, stability and maneuverability are simultaneously available.

To further facilitate the full and convenient use of our boat, we have designed a uniquely constructed permanently attached fold down boarding ladder which is shown in detail in FIGS. 7 and 8. The ladder is supported from two parallel side members represented, by the numeral 26, which may be fixedly attached to the transom 12c by conventional bolts or woodscrews. The lower end portions of each of the side members is suitably apertured with a rod member 27 rigidly anchored therebetween. A pair of rotatable brackets 28 are located on rod member 27, there being one bracket adjacent the inner opposed sides of each of side members 26. To facilitate assembly, the brackets are centrally apertured in the circular portions thereof and conveniently sized so that when same has the rod member extending through the apertures, the brackets may be conveniently swung either up or down respect to fixed rod member 27 and, as will be seen, through an arc determined by the outer peripheral edge of the circular portions of the brackets. Tubular bars 29 are weldedly attached to one surface of

brackets

28 and 29a and extend tangentially away from rod 27.

Step rungs

30 and 31 are likewise welded transverse to the upper and lower end extremities of the tubular bars 29. A circular contacting rod 32 is weldedly connected to the inner surface of rod 27 so that same is located between rod 27 and transom 12c and which may be used to operatively position the ladder either in its unfolded or stored position.

In operation, FIG. 7 shows the ladder folded up as it would be in the case when the boat is moving with or without skiers being towed from same. The solid line portions of the ladder in FIG. 8 indicate that when same is folded up, the upper ladder rung 31 contacts the upper surface of contacting rod 32. When the ladder is folded down to facilitate a swimmer or skier boarding the boat, the lower rung 30 will be swung in a counterclockwise direction (as shown in FIG. 8) so that a projecting contact lug 28a, which forms a portion of bracket 28a, swings to the underside of contacting lug 32 and abuts same with its new upper surface. In this manner, the ladder structure will quite easily support one seeking to board the boat with the entire unitary structure being braced against itself and with

rungs

30 and 31 optimally located to facilitate the normal boarding procedure. Of course, when the ladder is no longer needed, it may be manually moved to the solid line position shown in FIGS. 7 and 8 or the forward movement of the power boat will likewise swing an extended ladder in a clockwise (FIG. 8) or folded up position. In this manner, the ladder is maintained conveniently out of the way when not needed, yet, is permanently attached to the boat and will not be lost overboard or mislaid when it is needed.

We have found that the seating facility (pedestal seating structure 16) offers several advantages over the conventional cavity-type seating in a monohull boat. For instance, the operator and observer are up above the water surface with the operator located at the forward portion of the boat rather than at the rear. Likewise, with the trim tabs reacting so as to quickly locate the boat in its planing attitude (that being on the forward two-thirds portion of each hull) and with the normal running attitude being with the bow or forward portion of the boat in a relatively horizontal plane, the vision of the operator is not obscured by a raised bow as so often happens with monohull crafts and similar structures.

Not the least of the inherent advantages to the power boat described above is the motorcycle-type steering mechanism of which handlebar 17 forms an integral part thereof. FIG. schematically shows our steering linkage which has particular utility with the catamaran disclosed immediately above. For instance, the steering column (not shown) is, of course, movable with the handlebars and has a first bellcrank 33 attached thereto so that it is movable in accordance with the moving of handlebar 17. The end portion of the bellcrank has shaft 34 connected thereto and which operates to translate handlebars movement to the rear portion of the boat and more particularly to a second pivotally mounted bellcrank 35. Bell crank 35 may be mounted on a pivotal mount 35a in any convenient and conventional manner, however, the rearwardly turned portion of bellcrank 35a will include a rod 36 weldedly attached thereto with

rollers

36a and 36b affixed to each end portion thereof.

As is common with most power boats, the motor M of our powered catamaran is utilized as a steering rudder as well as a means to propel the boat. In this manner, the motor is conventionally swivelly mounted on the transom and will have an endless steering cable 37 affixed to the forward portion thereof. Cable 37 is supported in a substantially horizontal plane by rollers 37a and is under sufficient tension so that the cable is not permitted to droop. Likewise, the forward rollers 37a support the cable 37 in contact with rollers 36a and 3612 which, as suggested above, are movable with bellcrank 35. In this manner, when handle bar 17 is rotated, its rotative movement is translated from bellcrank 33 via rod 34 to bellcrank 35 and onto the rod 36. Since rod 36 extends substantially parallel to cable 37 when the boat is steered along its lubber line or straight ahead (see FIG. 10), a movement of the handlebar either to the right or the left will accordingly swing

rollers

36a and 36b, respectively, into contact with cable 37 thusly pivoting motor M in its proper direction to facilitate the steering of the boat. As shown in FIG. 10, when handlebar 17 is turned to the right, bellcrank 35 is moved about its pivot pin 35a to the broken line position (in a counterclockwise direction). The arcuate movement of bellcrank 35 swings the upper roller 36a against steering cable 37 moving same inwardly and downwardly within the perimeter of the endless steering cable loop. This, of course, swivels motor M in a counterclockwise direction and resulting in the boat being steered to the right. With the rod arm 36 adding additional leverage onto the movement of cable 37, it is not necessary to move handlebar 17 so dramatically in order to negotiate simple turns either to the right or to the left, thusly cooperating with the stability features of the boat design to result in an extremely maneuverable craft.

From the foregoing, it will be seen that this invention is one well adapted to attain all of the ends and objects hereinabove set forth together with other advantages which are obvious and which are inherent to the structure.

It will be understood that certain features and subcombinations are utility and may be employed without reference to other features and subcombinations. This is contemplated by and is within the scope of the claims.

As many possible embodiments may be made of the invention without departing from the scope thereof, it is to be understood that all matter herein set forth or shown in the accompanying drawings is to be interpreted as illustrative and not in a limiting sense.

Having thus described our invention, We claim:

1. A boat having two spaced apart hulls interconnected by a substantially flat deck, said boat comprising:

at least one seating means substantially centered along the longitudinal center line of said deck, said seating means extending above the horizontal plane of said deck and adaptable to be straddled, said hulls each having a substantially vertical step therein at a location approximately one-third of the length of said hulls, said step dividing the lower surface of each hull into two adjacent surfaces lying in substantially parallel planes, and means for facilitating the movement of said hulls from an attitude where both adjacent surfaces contact the water to a planing position with substantially only that portion of said hulls forward of said step in said water contacting position.

2. The invention as in claim 1, wherein said boat includes a motor mounted on same, same being operable to propel said boat through the water, and means for protecting sad motor from turbulence as said boat is being propelled.

3. The invention as in claim 2, wherein said boat includes a motor well located adjacent the aft portion of same and wherein said protecting means includes a motor fairing interconnected with said motor well and positioned forwardly of the location normally occupied by said motor.

4. The invention as in claim 2, wherein said boat includes a handlebar steering mechanism located at the forward end portion of said seating means, said handlebar interconnected by a mechanical linkage with said motor and operable to position said motor for steering purposes in accordance with the movement of said handlebar mechanism, said motor linkage including a means for facilitating the control of the steering movement of said motor so that relatively short ratio turns of said handlebar steering mechanism positively controls the steering movement of said motor.

5. The invention as in claim 4, wherein said linkage between said motor and said handlebar steering mechanism includes a bellcrank pivotally movable in accordance with the movement of said handlebar steering mechanism, a steering cable interconnected with said motor, a rod means interconnected with said bellcrank and contacting said steering cable to effect the movement of said steering cable and said motor with the movement of said bellcrank.

6. The invention as in claim I, wherein said hull planing means includes at least one trim tab hingedly connected to said boat and hydraulic means for positioning sad trim tab in an optimum position to move said boat onto the forward planing surfaces of said hulls.

7. The invention as in claim 6, wherein said boat includes at least one trim tab adjacent the rear end extremity of each of said hulls, and wherein said hydraulic means has a foot pedal located adjacent said seating means, said foot pedal operable to operate a hydraulic ram associated with each trim tab in accordance with the position of said foot: pedal.

8. The invention as in claim 7, wherein said trim tabs are movable to any water contacting operating position each time said foot pedal is fully depressed, said trim tabs having three operable water contacting positions, each of which results in the movement of said boat to the forward hull planing position.

9. The invention as in claim 1, wherein said boat includes a keel plate located at each step position of said hulls said keel plate operable to obviate sliding of the boat as the turns are negotiated or to maintain a steady course with minimum drift.

10. The invention as in claim 1, wherein said boat includes a foldable ladder fixedly attached to same, said ladder including a horizontal rod fixedly attached to said boat, at least two brackets pivotally attached to said rod, said brackets having at least two contacting surfaces wherein one of said surfaces contacts a contacting rod fixedly attached! to said first mentioned rod when in a folded-up condition and said other of said contacting surfaces contacting the lower portion of said contacting rod when in a folded-down position.

Claims

1. A boat having two spaced apart hulls interconnected by a substantially flat deck, said boat comprising: at least one seating means substantially centered along the longitudinal center line of said deck, said seating means extending above the horizontal plane of said deck and adaptable to be straddled, said hulls each having a substantially vertical step therein at a location approximately one-third of the length of said hulls, said step dividing the lower surface of each hull into two adjacent surfaces lying in substantially parallel planes, and means for facilitating the movement of said hulls from an attitude where both adjacent surfaces contact the water to a planing position with substantially only that portion of said hulls forward of said step in said water contacting position.

6. The invention as in claim 1, wherein said hull planing means includes at least one trim tab hingedly connected to said boat and hydraulic means for positioning sad trim tab in an optimum position to move said boat onto the forward planing surfaces of said hulls.

7. The invention as in claim 6, wherein said boat includes at least one trim tab adjacent the rear end extremity of each of said hulls, and wherein said hydraulic means has a foot pedal located adjacent said seating means, said foot pedal operable to operate a hydraulic ram associated with each trim tab in accordance with the position of said foot pedal.

10. The invention as in claim 1, wherein said boat includes a foldable ladder fixedly attached to same, said ladder including a horizontal rod fixedly attached to said boat, at least two brackets pivotally attached to said rod, said brackets having at least two contacting surfaces wherein one of said surfaces contacts a contacting rod fixedly attached to said first mentioned rod when in a folded-up condition and said other of said contacting surfaces contacting the lower portion of said contacting rod when in a folded-down position.