Trimaran with extensile hulls

Abstract

 This invention relates to a multihull boat (1) (trimaran), which has multiple hulls (3,4,5,6,7) connected to the main body (2) by connectors (8,9,10,11,12,13,14) with piston/cylinder mechanism allowing the hulls (3,4,5,6,7) to move longitudinally and transversely. It comprises a main body(2), two extensile side hulls (3,4) connected to the main body (2) via side hull connectors (9,10,11,12), two extensile rear hulls (5,6) connected to the side hulls (3,4) via rear hull connectors (13,14) and one front hull (7) connected to the main body (2) via front hull connector (8).

Description

Field of the Invention

[0001] This invention relates to boats, and more particularly trimarans with extensile hulls.

State of the Art

[0002] Trimaran is a marine vessel which is composed of a main hull and two side hulls parallel to it. Trimarans are used for long years due to its reliability in terms of balance, speed and comfort properties accrued by its hulls. However, due to its large width, some problems arise like difficulty of movement in marinas and similar narrow areas, lack of maneuverability, difficulty of being carried by a trailer and difficulty in boarding. Solutions for these problems are proposed in different patent documents.

[0003] US Pat. No. 5107783 discloses a trimaran which has side hulls capable of moving up and down. The motion is provided by a piston cylinder arrangement. By this means, contact of side hulls with the water is cut off so that the boat can move through narrow paths and get closer to berth. However, the distance between the side hulls and main hull is limited by the width of boat; so, higher stability and speeds can not be reached, which is available at the present invention.

[0004] US Pat. No. 2678018 shows a trimaran which has 3 position side hulls on both sides of the main hull. There is a mechanism to provide an option to hold the side hulls in two different distances to the main hull and also to hold the hulls underneath the main hull by rotating them 90 degrees around an axis parallel to the motion direction of boat. By this means, an opportunity not only to have a higher stability movement, but also to keep the side hulls under the main hull for decreasing the width of boat to let it move through narrower paths is created. But while the mechanism to get the side hulls under the main hull is operating, an unbalance of boat will occur. Also the profile of the boat under water is not appropriate in terms of fluid dynamics. Another drawback of this invention is the difficulty of using the "swing-wing" mechanism while cruising since the mechanism is operated by loosening/tightening the screws and nuts manually.

[0005] The underwater boat profile problem of US Pat. No. 2678018 is solved by US Pat. No. 5277142. By compromising the advantage of having 2 different sides hull positions that US2678018 has a better underwater profile when the side hulls are collected under the main hull is obtained. However, the extended distance between main and side hulls is fixed and limited by the length of rotating arm. In the present invention, the extended distance, which is increased when compared to US Pat.No. 5277142 is adjustable so that a more stable cruise is obtained

[0006] Both US Pat.No. 3937166 and 5235925 disclose trimarans that have a lever arm mechanism (a pivot structure interconnecting the main hull and the retractable hull) that can pivot the side hulls to lie alongside the main hull to compact the boat by making the side hulls almost vertical near the main hull. This also results in availability of cruising in narrow paths but the compacted structure has a risk of getting damaged while being carried by a trailer due to its shape when compared to the present invention, which is safer to handle since it collects the side hulls beneath the main body. Also, it is more difficult to maneuver with the compacted mode of both US Pat. No. 3937166 and 5235925 since it has a balance problem due to vertically lying side hulls. Another disadvantage of the boats explained in US Pat. No. 3937166 and 5235925 with respect to the present invention is that they do not have front and rear hulls to obtain more stability and they have only two positions of the side hulls, "in use" and "not in use", unlike the present invention that has adjustable distance of hulls.

[0007] US Pat. No. 4730570 shows a trimaran that has extensile hulls using sliding crossarms. In this invention, side hulls are fixed in desired position on the sliding axis by screws and nuts manually. Therefore it should be done before setting sail. It is not possible in this invention to adjust the hull position while on cruise, which makes computerized control system implementation impossible. However, the present invention allows the crew to adjust the hull positions while cruising and also implementation of a computerized control system adjusting the hull positions according to the boats dynamic behavior is available.

[0008] Another invention using the swing-wing mechanism is disclosed in US Pat. No. 4172426. The hulls can extend by the rotation of an arm with the aid of tension cables and hinges. The mechanism used in this invention requires dynamic tension cables to be stretched between side hull and the main one all along the hulls, which is not very acceptable for crew safety. The invention also has a disadvantage of only two positions available for the hulls: extended and compacted, and also the extended length is limited by the length of the rotating arm. Therefore implementation of a computerized control system is not appropriate for this invention. Another drawback of this invention is deficiency of front and rear hulls.

[0009] US Pat. No. 5647294 shows a boat with floaters on both sides. These floaters are connected to the main boat via long rotating arms that can come alongside of the main boat. The mechanism has an apparatus that can increase the length of arm to some extent manually. The invention is more appropriate for small boats and these floaters have far cry effect on the stability when compared to the hulls of present invention. Also the mechanism used in US Pat. No. 5647294 is not suitable for computerized control. Also the floaters of this invention do not decrease the contact surface of the system with water unlike the present invention, at which the main body does not have contact with water (contact with water is only at side, front and rear hulls).

Object of the Invention

[0010] The aim of this invention is to provide a boat that has low friction area and high stability by using a main body that does not have contact with the water, side hulls that can extend to both sides of main body, rear hulls that can extend backwards from the side hulls and a front hull that can extend to the front of the main body.

[0011] Another aim of this invention is to provide a boat which can retract all of its hulls beneath the main body so that it can stay in marinas with lower prices, it can easily cruise on narrow paths, it has increased maneuverability and it is available for being carried by trailer.

[0012] Another aim of this invention is to provide a boat that has hulls which are easily extended to desired positions, so that adjustments for varying conditions affecting cruise conditions such as water and weather conditions while on cruise can be made for a more stable, safer, faster and more comfortable cruise, and also to make the adjustments available for manual or computer based control.

[0013] Another aim of this invention is to provide a more comfortable cabin by having an increased volume above water so that the cabin can be made larger

Explanation of the Figures

[0014] Attached figures illustrate a sample embodiment of the present invention, which do not limit the scope of protection and wherein:

Figure 1. A bottom view of the present invention with all hulls open (extended)

Figure 2. A bottom view of the present invention with all hulls retracted

Figure 3. A side view of the present invention with all hulls open (extended)

Figure 4. A side view of the present invention with all hulls retracted

[0015] All pieces in the figures are enumerated and named one by one below:

(1)

Trimaran

(2)

Main body

(3)

Left side hull

(4)

Right side hull

(5)

Left rear hull

(6)

Right rear hull

(7)

Front hull

(8)

Front hull connector

(9)

Left side hull first connector

(10)

Left side hull second connector

(11)

Right side hull first connector

(12)

Right side hull second connector

(13)

Left rear hull connector

(14)

Right rear hull connector

(15)

Housing of front hull connector

(16)

Housing of right side hull first connector

(17)

Housing of left side hull first connector

(18)

Housing of right side hull second connector

(19)

Housing of left side hull second connector

(20)

Housing of left rear hull connector

(21)

Housing of right rear hull connector

Description of the invention

[0016] The present invention is about a trimaran (1) comprising: a main body (2); extensile side hulls (3,4) which are connected to the main body (2) via connectors (9,10,11,12) including piston cylinder mechanisms; extensile rear hulls (5,6) which are connected to the rear end of side hulls (3,4) via connectors (13,14) including piston cylinder mechanisms and a front hull (7) connected to the main body (2) via extensile front hull connector (8). The front hull (7) can extend towards the positive cruising direction, the side hulls (3,4) can extend towards the axes perpendicular to the positive cruising direction and parallel to water surface and the rear hulls (5,6) can extend towards the negative cruising direction. All of the mentioned connectors (8,9,10,11,12, 13,14) are slidably moveable parts. Front hull connector (8) is nested in the housing of front hull connector (15) lying all along below the main body (2). Side hull connectors (9,10,11,12) are nested in the housings (16,17,18,19) lying below the main body in the direction perpendicular to cruising direction and parallel to the water surface, which are designed accordingly not to coincide the housing of front hull connector (15). In the sample embodiment, housing of side hull connectors (16,17,18,19) are positioned beneath the main body (2) and housing of front hull connector is positioned under the side hull connector housings (16,17,18,19). The housings of opposing connectors of side hulls (16 vs. 17, 18 vs. 19) may be on the same axis or, more preferably, may have an offset in main cruising axis. In the preferred configuration, i.e. when they have an offset, they can be made longer (up to the width of the trimaran) and this results in availability of using longer pistons so that the side hulls (3,4) can extend more to the sides and the stability increases (so does the max speed allowed).

[0017] Rear hulls (5,6) can extend towards the negative cruising direction as mentioned earlier. This sliding motion is provided by the motion of rear hull connectors (13,14) nested in the rear hull connector housings (20,21) located inside the side hulls (3,4).

[0018] As a result of the ability to retract all of the hulls (3,4,5,6,7) and connectors beneath main body (2), the trimaran (1) can be carried by trailer, it can stay in marinas with lower prices and it can cruise in narrow paths.

[0019] In a sample embodiment of the invention, all of the mentioned hull (3,4,5,6,7) motions are made by sliding of pistons actuated by separate electric motors and worm screws for each piston. The worm screws transmit the motions created in the electric motors to the pistons. Preferably, manual capstans are used at each sliding part as a precaution for unavailability of using the powered sliders (motor breakdown, electric shortage etc.).

[0020] It is also possible to use different systems that can do the same work instead of electric motor and worm screw configuration, such as hydraulic or pneumatic systems.

[0021] In the present invention, each of the side hulls (3,4) and the front hull (7) are designed to carry the weight of trimaran (1) by itself. In a sample embodiment, polyester coated wood is used as material for main body (2) and the hulls (3,4,5,6,7).

[0022] When all of the hulls (3,4,5,6,7) are extended to their maximum capacity (as seen on figure 1), they provide the boat with highest statically and dynamically stability, thus gaining the boat capability of cruising at higher speeds. Moreover, with the use of hulls (3,4,5,6,7), contact area of the boat with water decreases resulting in lowered friction forces. In addition to these, as a result of high buoyancy effect of the hulls (3,4,5,6,7), it is possible to build a higher volume, therefore more comfortable cabin.

[0023] All of the hulls (3,4,5,6,7) have the ability of being hold in the desired extension length with the aid of piston cylinder mechanism usage. The ability of the hulls (3,4,5,6,7) to be extended/retracted fast and easily gives the user possibility of making optimization between high stability/speed and maneuverability/cruising in narrow paths. Also, safer cruise can be obtained by adjusting the hulls' (3,4,5,6,7) positions for different weather and water conditions.

[0024] In addition to the possibility of adjusting hull (3,4,5,6,7) positions manually, a computer based control system ,which uses inputs affecting cruise conditions such as weather and water conditions as inputs, can also be implemented to control the hull (3,4,5,6,7) motions is also available.

[0025] Optionally, by setting up nets between side hulls (3,4) and main body (2), larger areas for use (for sunbathing etc.) can be obtained on the deck. Mentioned net is connected to a reel and becomes available for use by being stretched with the extension of side hull connectors (9,10,11,12).

[0026] Optionally, as a precaution for secure use, a mechanism using sensors can be implemented on the net system that prevents retraction of side hulls (3,4) while the net is in use, i.e. there is a weight on the net. Again optionally, a mechanism or algorithm that prevents the rear hulls (5,6) to be extended while there is not enough clearance, i.e. the side hulls (3,4) are not extended enough.

[0027] Optionally, by using a control system, which uses inputs coming from sensors (pressure sensor, accelerometer etc.) located on the hulls (3,4,5,6,7) and actuates small stroke pistons located between the connectors (8,9,10,11,12,13,14) and hulls (3,4,5,6,7), cabin stability can be provided at wavy water. Another option to keep the cabin stable is to use shock absorbers instead of the pistons, which damp some of the forces caused by waves.

Claims

1. A marine vessel comprising a main body (2), side hull connectors (9,10,11,12) that can be extracted/retracted (in the axis perpendicular to cruising axis and parallel to water surface) and that is nested in side hull connector housings (16,17,18,19) lying beneath the main body (2), side hulls (3,4) connected to the mentioned side hull connectors (9,10,11,12), rear hull connector housings (20,21) inside these side hulls (3,4), rear hull connectors (13,14) that can be extracted/retracted (in the axis parallel to both cruising axis and water surface) and that is nested in these rear hull connector housings (20,21), rear hulls (5,6) connected to these rear hull connectors (13,14), front hull connector housing (15) lying beneath the main body (2), front hull connector (8) that can be extracted/retracted (in the cruising axis) and that is nested in front hull connector housing (15), a front hull (7) connected to this front hull connector (8).

2. A marine vessel according to claim 1, wherein the control of one or more hulls' (3,4,5,6,7) extension adjustments are made by a computer based control system using inputs affecting cruise conditions such as weather and water conditions.

3. A marine vessel according to claim 1 and claim 2, comprising shock absorbers and/or pistons located between one or more of the connectors (8,9, 10,11,12,13,14) and hulls (3,4,5,6,7), a control system to control said pistons and sensors located on relevant hulls (3,4,5,6,7) sending information to the said control system.

Drawing