A multi-hull vessel has a center section and a plurality of float arm assemblies disposed on opposite sides of the center section. The float arm assemblies are pivoted so as to be movable upwardly or downwardly. Each float arm assembly comprises upper and lower arm arrangements, each including inner and outer segments joined by a pivot. The outer segment of the lower arm arrangement includes a float. To raise the arms assembly, a rigging line is provided which extends from the center section to the outer segment of lower arm arrangement and is disposed above the intermediate pivot of the lower arm arrangement and below the intermediate pivot of the upper arm arrangement. The rigging line is oriented to produce a lifting force on the lower arm arrangement having a larger component in horizontal direction than in the vertical direction.
RELATED APPLICATIONS
This is a Continuation-in-Part of now-abandoned U.S. Ser. No. 07/027,208 filed March 24, 1987 which, in turn, is a Continuation of now-abandoned U.S. Ser. No. 06/751,382 filed Jul. 3, 1985.
BACKGROUND OF THE INVENTION
This invention relates to multihull vessels having a center section, which may be a cabin or other superstructure with or without an attached hull, a pair of outrigger hulls (hereinafter referred to as floats) oppositely spaced from the center section on pivotally mounted and jointed arms or outriggers (hereinafter referred to as float arms), and one or more masts mounted on the center section.
In contrast to a self-righting monohull vessel which maintains stability by having its center of gravity arranged below its center of buoyancy, a multihull vessel provides buoyancy to oppose heeling in the form of divided hulls or outrigger floats. A monohull sailboat with ballasted keel has no righting moment at 0 degrees of heel where heeling moment is maximum, has maximum righting moment at 90 degrees of heel where heeling moment on the sailplan vanishes and is unstable at 180 degrees of heel. A multihull vessel has large initial stiffness or resistance to heeling due to the lateral displacement of the center of buoyancy, but the righting moment decreases as the angle of heel increases while more of the bottom of the vessel is exposed to the forces of wind, and the vessel is more stable at 180 degrees of heel than at 0 degrees unless additional buoyancy is provided above the center of gravity of the upright vessel. Unless the beam of the vessel can be reduced, a very large righting moment is required, usually in the form of unavailable external leverage, to bring the vessel back past 90 degrees of heel.
A solution to the problem of multihull capsizing, comprising means for placing movable outrigger floats beneath and within the cross-sectional extent of the center section of the capsized vessel, thereby rendering the vessel unstable in a capsized position, is provided in U.S. Pat. No. 4,159,006 issued 26 Jun. 1979 and U.S. Pat. No. 4,457,248 issued 3 Jul. 1984, both to this inventor. In addition to providing a method for righting a capsized multihull vessel inherently superior to any disclosed in the prior art, the inventions described in the two cited patents provide a degree of adjustability in the position of standing rigging as well as in the position of the outrigger floats making possible many additional improvements in sailing performance, safety and comfort.
The present invention provides feedback means permitting compensating interactive adjustments in the relative positions of elements of standing rigging and outrigger float connection apparatus, such adjustments being activated by changing forces of wind and water on the floats and sails, to produce such additional benefits.
It is an object of the above cited patents to provide means for varying the positions of floats from their normal extended positions, laterally spaced from the center section to provide stability in normal sailing attitudes, to positions raised above the center section, i.e., beneath the center section when the vessel is fully capsized, thereby rendering the vessel unstable in a inverted or capsized condition, and also to positions lowered to the sides of or below the center section of the upright vessel, thereby reducing the beam for various purposes such as trailering or accommodating a narrower berth.
It is another object of the above cited patents to provide means for adjusting the floats to and maintaining them in various orientations with respect to the center section at all heights between the fully raise and the fully lowered positions, which means may be contained inboard and in-place as permanent components of the structure and rigging, require no equipment to be attached or detached from the floats or arms to effect the adjustments and require no releasable restraints and a minimum of fixed limits on the rotation around joints within the float arms. Applications dependent on float adjustability, in addition to those mentioned for reducing the beam of the vessel with the floats in their extreme positions, include alterations in float height, distance from the center section and attitude relative to the center section for fine adjustments to the vessel's performance in different operational circumstances and for more radical changes in the vessel's performance characteristics. Such changes include lifting the main hull of a trimaran nearly clear of the water to gain any performance advantages of a catamaran and rotating the floats to bring planing or hydrofoil surfaces into operational positions.
It is a further object of the cited patents to make elements of the standing rigging adjustable such that the position of a mast may be varied from fully vertical to fully horizontal (in either the fore or aft directions) and such that adjustments of the mast can be carried out in a variety of ways, independently of or in conjunction with adjustments of the floats. Beside independent lowering of the mast for stowage and re-raising of the mast from the stowed position, the applications include: "lowering" the mast as the floats are "raised" in a capsize recovery for the purpose of pivoting shrouds out of the way of the floats; "lowering" the mast to the deck in a capsize recovery for the purpose of utilizing shrouds to life the floats, with motive force possibly being supplied by masthead flotation; causing the mast to be re-raised during capsize recovery by the re-lowering of the floats and leaving the mast stowed on the deck as floats are re-lowered during capsize recovery, with "raising" and "lowering" referred to the vessel in its upright position. It is a further object of the above cited patents to bring control of rigging or other equipment for adjustment of float and mast position to a central location where this control can be readily and selectably exercised by the crew for various operations while underway or during capsize.
It should be noted that in all of the following description, terms such as "up" and "down" or "raising" and "lowering" will be assumed to be defined in terms of the upright vessel, unless otherwise noted, even when it is being considered to be upside down in the water.
The preferred embodiments of the inventions disclosed in the cited patents include float arm assemblies, each pivotally connecting a float and the center section and each comprising a pair of arms, each arm comprising pivotally connected arm segments. These embodiments also include pairs of adjustable-length rigging lines connected between the pairs of arms in each float arm assembly and the center section and led to a central location for control by the crew of the relative positions of all float arms segments. They further include adjustable-length rigging lines connected between a mast pivotally connected to the center section and the center section and optional adjustable rigging lines connected between this mast and each of the floats.
These two patents do not fully describe how seemingly independent rotations at a multiplicity of pivot connections within float arm assemblies connecting the floats to the center section in the preferred embodiments of the basic invention can be simultaneously controlled with no more than two adjustable means in each float arm assembly to move the floats between desired positions and to maintain them at desired spacing from and orientation to the center section in each of these positions while the floats are being acted upon by variable and fluctuating external forces.
It is an object of the present invention to provide an arrangement of dual rigging lines connected between arm segments in each float arm assembly whereby: the float arm segments may be manipulated into desired orientations relative to one another, the resulting configuration of float arm assemblies will maintain the floats at desired positions relative to the center section in opposition to expected external forces on the floats and controllably small deviations from the desired positions will occur in response to expected fluctuations in such forces. The present invention provides control over the orientation of arm segments within float arm assemblies with a method and a concept not described and not anticipated in the two prior patents of this inventor.
It is a further object of the present invention to provide control means interconnecting the adjustable rigging from the separate float arm assemblies, such control means including manual means permitting common and equal as well as separate and independent movement of the outrigger floats between desired positions, the control means further including resilient reactive means connected between any of the adjustable rigging lines and any other rigging lines, the center section, the floats or the float arms, the resilient means keeping rigging lines under tension and operating reactively and independently of the manual means to permit adjustment within any one float arm assembly to sudden and variable external forces and to permit compensating adjustment within other float arm assemblies for purposes of maintaining the floats at desired positions relative to an irregular sea surface while minimizing changes in motion (or orientation) of the vessel's center section.
It is a further object of the present invention to provide a mast pivotally connected to the center section and permitting rotation of the mast toward either side of the center section in addition to rotation toward the fore or aft end of the center section and also to provide adjustable length control means between the mast and structural components of the vessel, such control means including manual means for controlling the rotation of the mast relative to the center section and further including resilient means within the adjustable length control means and interconnected with the float arm rigging control means or connected to float arm segments to permit interactive and compensating adjustments within float arm assemblies in reaction to rotation of the mast caused by sudden changes in the force of the wind on the sails, the purpose of the adjustments in float position being to minimize the effect of these flutuating forces on the motion of the vessel's center section or of the mast.
SUMMARY OF THE INVENTION
According to the present invention, there is provided a multihull vessel comprising a center section, which may be a cabin, platform or other superstructure with or without an attached center hull; a pair of floats oppositely spaced from the center section; a plurality of float arms connecting the floats to the center section and consisting of segments arranged in fore and aft float arm assemblies for each float and pivotally connected at their ends to the center section, to the floats or to other float arm segments; rigging lines connected between locations on or within float arm assemblies, the floats or the center section and led via pulleys or other guides within the float arm assemblies and the center section to means for controlling this rigging from a central location; at least one mast, normally connected pivotally to the center section; elements of standing rigging effectively adjustable in length, with the termination of this rigging or, optionally, of additional rigging, attached to the standing rigging or to pulleys riding on the standing rigging, being led to means for controlling this rigging from a central location within the center section and finally, controls in a central location for adjusting independently or simultaneously, in various selectable combinations, the length of rigging lines to vary the positions of either or both floats and the mast by any desired amount from fully raised positions to fully lowered positions.
A particular embodiment of the invention is a sailing trimaran (having a center hull) with double arm float arm assemblies jointed twice in the upper arms and pivotally connected at either end and jointed once in the lower arms and pivotally connected at the inboard ends. A mast is pivotably to the center section at a joint near the deck for rotation in both fore and aft directions as well as sideways. This embodiment will now be described, by way of an example, along with various alternative or optional features and extensions of the basic structure, with reference to the accompanying drawings.
An improved version of the Float Connection Assemblies as described in U.S. Pat. No. 3,937,166, for the retraction of a trimaran's stabilizing floats to be alongside the trimaran center hull for trailering or Marina docking. The improvement consists of a variable length Upper Pivoting Guide Frame, that when varied in length will allow a trimaran float being retracted by the Float Connection Assemblies to assume a different, higher and more favorable position, to prevent marine growth on the floats' sides, particularly the topsides above the normal waterline when retracted. This allows a trimaran incorporating this improved Float Connection Assembly to be easily converted from a trailerable configuration, to a more suitable Marina docking configuration, without the problem of underwater growth on the retracted float's side.
Folding trimaran which is symmetrical in relation to its median longitudinal axis and comprises a central hull, equipped with a mast, and also two lateral floats, which are connected to the central hull by at least one connecting arm. The trimaran can be moved between a first position in which the connecting arms are unfolded approximately horizontally on each side of the central hull, substantially perpendicularly to the longitudinal axis of the latter, and a second position in which the floats are folded along the central hull in such a manner as to reduce the space requirement. The trimaran has at least two connecting arms arranged symmetrically to define a maneuvering pair extending as far as the median horizontal axis. This pair is one on the other or separate at a place and are connected to the mast by one or two sliding carriages which can be moved in translation along the mast in order to enable the trimaran to be moved from the sailing position into the mooring position or vice versa by folding the two floats either at the same time or separately.
This invention refers to single hull/multi-hull sailing boats. Two suitably shaped floats are laterally applied to the hull of single hull boats; they slide from top to bottom along suitable guides. The lateral hulls of multi-hull boats also slide from top to bottom along suitable guides. This device includes a sail mast moving in function of the wind lateral thrust on sails and the mast movement makes the lee float or hull to sink. The lee float or hull sinking is used to oppose both the boat heeling and drift. The invention application gets these advantages: improvement of the boat comfort and safety, increase of sails efficiency and optimization of hull hydrodynamic performances.
A multi-hull watercraft, such as a catamaran or trimaran is constructed to facilitate the righting thereof following a capsize. By providing a pivot connection between the hulls and the cross-members, in accordance with one method, it is possible to right the capsized vehicle by piecemeal rotation of the hulls through 180.degree. from an inverted to an upright disposition. Following this maneuver, the mast may be either rotated up and out of the water to an erect disposition or, alternatively, the mast can be jacked vertically through the deck. In accordance with a second method, the multiple hulls are interconnected by articulated, extendable and contractible cross-members and righting is achieved by sequentially reducing the beam of the craft, canting its buoyant mast from vertical so that the watercraft will roll so as to be floating on one hull and on the buoyant mast and then while canting the mast in the opposite direction again extending the cross-member to increase the beam such that a rotational moment about the one hull is created sufficient to raise the mast out of the water to an upright disposition.
A boat that has a central hull, a pair of floats, and a pair of outrigger spars for supporting the floats on each side of the hull. The outrigger spars are adjustably mounted on the hull so that the floats can be adjustably placed in a given range of positions that lie both (i) substantially spaced away outboard of the side beam of the central hull as well as (ii) substantially spaced rearward of the stern of the central hull. The floats are much smaller than the central hull, partly so that the central hull can be formed with storage recesses in the side-boards thereof for removably storing the floats in a stored position during non-use of the floats. The outrigger spars are preferably mounted to the central hull at or near the opposite rear corners thereof. Also, the outrigger spars are preferably mounted to the central hull for pivotal movement in generally horizontal planes. The boat further includes a set of locking mechanisms between the spars and the central hull, for releasably locking the spars in set positions. Additionally, the spars can be locked in position independently of each other and therefore need not be set in symmetric angles of divergence from the central hull.
