JPS59124480A - Hydrofoil - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

BACKGROUND OF THE INVENTION Field of the Invention This invention relates to sailing vessels, and more particularly to hydrofoil sailing vessels having wing sails.

In the past, efforts have been made to increase the operating characteristics of sailing vessels.

Early sailing ships were generally limited to sailing downwind. Although the ability to sail upwind generally increased, the development of hull, sail, and rigging design lagged behind. With the advent of sailing ships, it became possible to sail at right angles to the wind or even slightly upwind. However, from Kerr, the sailboat required a means to resist leeward drift and capsizing moments. These are caused by the lateral components of the forces produced by the sail. Several attempts have been made to improve sailboat design in the areas of upwind ability and speed possibilities. Hydrofoils have been used to raise the hull out of the water, greatly reducing hydrodynamic drag and resisting downwind cross currents. A variety of hydrofoil geometries have been developed using fully submerged or sloped, water-piercing hydrofoils to increase speed and improve stability. However, such designs had excessive low speed drag and required strong winds and high speeds to lift the hull out of the water. At high speed,
Most hydrofoil sailboats suffer from air flow over the leeward hydrofoils which can cause the hydrofoils to lose lift and cause them to suddenly submerge and eventually capsize.

Improving the ability of sailboats to sail directly against the wind was accomplished through the use of wing sails and even more rigid wings using an effective wing shape. Various Hiko non-vertical sails were also developed to reduce capsizing moments. The wing sail and rigid wing generate lift at lower angles of attack than possible with conventional Bermuda sails, allowing the sailboat to point into the wind by up to 18 degrees. The symmetrical wing shape is fixed and simple, but produces about lθ% less lift than a similarly sized Bermuda sail. The asymmetric wing shape can generate up to 50% more lift than a similarly sized Bermuda sail.

However, these asymmetrical shapes are better handled by sailing ships (ta
Cks) or must be reversed when reversing direction. Furthermore, the mechanism developed to do this is complex and heavy.

Improvements have been made in the performance of hydrofoil sailing vessels over the past several years. However, improvements to hydrofoil sailing ships have met with varying degrees of success. The reason for this is that there are drawbacks with respect to control, stability and aero/hydrodynamic efficiency.

SUMMARY AND OBJECTS OF THE INVENTION It is an object of the present invention to provide a hydrofoil sailing ship that does not have the above-mentioned drawbacks.

Another object of the invention is to provide a high speed hydrofoil sailing vessel with improved operating characteristics. The hydrofoil sailboat of the present invention includes bow and stern water-piercing hydrofoils and an asymmetric sail. Both hydrofoils have an inverted arch shape, a bow-shaped (i.e., chord-bounded arc) cross-section, and a high aspect ratio (
It has a wing length/area) and is interconnected by a deck and a hull tube.

The wing sail has a single rigid symmetrical top frame member and an asymmetrical bipartite articulated bottom frame member. The bottom frame member has paired symmetrical sections constrained to limited relative movement with respect to each other.

A sail sock (salIBock) is tensioned between the top and bottom frames and the forward section of the bottom frame member is movable relative to the sail sock. The sails are cantilevered and supported on a rotatable center mast.

Figure 1.2.8 shows a hydrofoil sailing vessel 10-1, for example, a blower (
Proa) is shown. This is a ship that sails equally well forward and backward. This ship is bow underwater - wing 12
It has a stern hydrofoil 14 and a wing sail 16 inclined toward the windward. The hydrofoils 12, 14 have an arcuate cross-section with sharp front and rear edges so that the wing operates equally well in the direction of inclination. Each hydrofoil 12, 14 is a high aspect ratio hydrofoil that penetrates the water surface and has a substantially U-shaped or inverted arch shape. The bottom of each hydrofoil 12.14 has a pair of skegs that provide lateral lift for the centerboard at high speeds.
'& installed. These heels are substantially symmetrical, as shown in FIG. These heels 18 are widely spaced and dimensioned so that when the ship lists, the heels remaining in the water provide adequate windward lift. A tip plate 20 provided at the bottom of each heel 18 increases the effectiveness of the heel, provides stability at the tip of the heel, and is made of crude lubricant (crud).
e5kid).

Hydrofoils 12, 14 are arranged spaced apart and parallel to the hull members 2.
Interconnected by 2.24. Each hull member 2.2, 24
For example, a section of thin-walled aluminum tubing is sealed with an end cap 26, such as a streamlined fiberglass cup or plastic buffer.

A deck plate 28 connects the hydrofoil 12 and the ends of the hull tubes 22,24. The deck plate 80 connects the hydrofoil 14 and the hull tube 22. ,2
Connect between the ends of 4. In a preferred embodiment, Detsuki [2B,
80 is made of fiberglass and is formed to wrap around the hull tube 22, 24 and is connected thereto, for example by a rivet.

Hydrofoil 12 and deck plate 28, hydrofoil 14 and deck @80
have similar external shapes and are interchangeable.

The wing sail 16 is attached to the deck@2B, 130 and the leeward hull tube 22 by a frame 82 and a mast bracket 42.

A frame 82, for example a rigid tetrahedral frame, has struts 84, 86, 88, 40.

One end of each strut 84,86 is attached to deck plate 28, and the other end of these struts is attached to mast bracket 42. One end of each strut 88.40 is attached to the deck vi80, and the other end of these struts is attached to the mast bracket 4.
Connect to 2. The lower end of the mast bracket 42 is connected to the leeward hull tube 22. Deck 442, such as a lightweight polypropylene material, is stretched across the tetrahedral frame to form a ramp deck for the sailboat operator's bunk. The deck 44 is secured to the hull tubes 22,24 by means of a strip 46, for example a buffer strip, which is tightened to the hull tube. Furthermore, the deck 44 is secured by strings 48 tied to the struts 84.36, 88.40. As described later, the wing sail 16 is attached to the mast bracket 42.
It is supported on a mast 50 rotatably provided.

The wing sail 16 has an asymmetric wing body, and its total length (sp'a
n) is approximately 11-12 feet (approximately 8.85-8.6
6 m) and includes a single top frame 52 and an articulated bipartite bottom frame 54. Frame 52.
j4 is supported on the mast 50. This mast, for example,
- A 7-inch diameter aluminum mast that stays in place and rotates freely. As shown in FIG. 4, the articulated bottom frame 54
has a front section 56 and a rear section 58. In the illustrated embodiment, for example, a top frame 52 and a bottom frame 5
4 is hollow, sealed for buoyancy, and made of glass fiber. Sail socks made of elastic material (5ail 5oc
k) 60 is strung high between the top frame 52 and the bottom frame 54. Top frame 52 is keyed to mast 50.

The bottom frame sections 56,58 are freely hinged to the mast rotation and can be pivoted 80 degrees out of plane to provide the desired asymmetric shape to the sail 16.

Bottom frame sections 56,58 are cantilevered from the mast 50. Section 58 is the lower girder strut (bo
om vang) 72 to alleviate cantilever loads. As shown in FIG. 4, the rear section 58 is cut out to form a front tongue 62, which is freely received within the cutout section 64 formed in the front section 56. Through hole 6 sized to freely accept mast 50
6 is shaped 1f on the rear part of the anterior section 56 in the resection section 64 and on the tongue piece 62 of the posterior section 58.
flt, the forward and aft sections are constrained with limited pivoting movement to the mast rotation. The rear section 58 is formed with a substantially precise cutout 68 to allow the front section 56 and the rear section 58 to pivot relative to each other. Mast 50 is received within mast bracket 42 and freely rotates therein.

When the ship is at sailing level, the aerodynamic center of lift is the sailing ship 10
mast 5 to keep it just above the hydrodynamic center of drag.
0 is tilted to windward, for example 86°.

Because the sail 16 is heeled, useful vertical lift is created, which reduces the apparent effective load on the sailboat and also reduces hydrodynamic drag. The wing sails 16 are balanced to avoid reducing high torque or pitching forces. Additionally, the wing sails are rotated just in front of the aerodynamic center of lift, which aerodynamic center is approximately i of the length of the bottom frame 54 behind the leading edge of the forward section 56, so that the wing sails 16 are nl When you are angry, feather (fe)
ather).

As shown in FIG. 5, the wing sail 16 has a thick nose.
ed) An asymmetrical wing body with a slightly tapered rear surface 67 in the pressure direction of this wing body. Although other airfoil cross-sectional shapes may be used, the preferred airfoil provides relatively high lift and low drag even at very low angles of attack. In the illustrated embodiment, the top frame member 52 has a symmetrical configuration with a relatively small chord. As mentioned above, the frame 52 is keyed to rotate together with the mast 50 which is rotatably provided within the mast bracket 42.

Sections 56, 58 of the bottom frame 54 are symmetrical members hinged freely around the mast 50, these sections pivoting out of the plane on each side and allowing the wingsail 1
6 resulting in the desired asymmetric shape.

The sail sock 60 is pulled tight on the top frame 52;
It is secured to the rear section 58 of the bottom frame 54. The sail sock 6o is held under high tension but is free to rotate around the front of the forward section 56 of the bottom frame 54. Tension in the sliding portion 80 of the sail sock 60 is maintained by a bottom lacing portion 79 which slides freely over the rounded bottom portion of the forward frame section 56. The wing sails 16 are thus articulated. Since the bottom frame 54 has a relatively large chord,
Its asymmetric shape affects the shape of the sail 16 except for the top. In order to minimize the drag caused by wing tip vortices,
Lower spar wing end plate (boom tip plate) 70
and an oval shaped frame 52. Lower girder end plate 70
impedes the air flow from the pressure fllL= of the wing sail 16 to the suction side. The frame 52 defines an elliptical wing tip that produces minimal induced drag. The use of the lower spar endplates 70 and the oval top frame 52 increases the apparent aspect ratio of the sail 16 and therefore reduces the overall induced drag force.

The operating characteristics of the sailing ship IO are as follows. That is, the buoyancy mode is experienced from 0-8.5 knots, the hydrodynamic mode is experienced from 3.5-14 knots, and the hydroplane mode is experienced from 14-85 knots. A wind of at least 6 knots will result in hydrodynamic levitation (1ift-ou)
t ). The design of the sailboat 10 is such that as speed increases, the hydrofoils 12.14 raise the sailboat further above the water, and most of the hydrofoil lift is generated by hydroplane pressure on the bottom side of each hydrofoil. It is a kimono. Even if at high speeds the suction or top side of the hydrofoil 12.14 becomes ventilated and loses hydrodynamic lift, there is sufficient residual hydroplane lift to support pitch stability. For example, 27
At Knott, hydroplane lift is approximately 80% of the total lift.

Fence or air gate? 4 is provided on the suction side of each submersible R12 to minimize drafts. In the illustrated example, each underwater Rl 2. , l4 has a shallow curve so that the large wing area remains submerged even at small submergence depths. Each hydrofoil 12
．． The geometry of 14 is such that the cross-sectional area gradually increases from the bottom to the top of the hydrofoil. i.e. hydrofoil buoyancy;
The chord length and cross-sectional area increase from the center of the hydrofoil to the ends. The geometry of the hydrofoils 12,14 creates an increasingly strong righting moment as the hydrofoils roll and pitch, giving the sailboat 10 dynamic stability in pitch and roll. The operator can change the position of the body and/or
The bow sway (progressing direction) of the sailboat 10 is controlled by changing the roll angle in accordance with the change in the angle of attack 6. As each hydrofoil 12, 14 approaches the free water surface, surface approach effects reduce lift and drag by approximately 50%, and a large foil area is required to compensate for the reduction in lift. The angle of attack that produces lift ranges from -4° to about 15°, with the most effective range being θ° to 5°, and 1° to 2° being optimal.

At low speeds, the inverted arch shape of the hydrofoil 12.14 resembles a conventional water-penetrating "v" shape, creating centerboard forces to counteract the sail-induced side forces. ing. This effect is lost at high speeds. This is because the submerged portion of the hydrofoil 12.degree. 14 is almost flat and horizontal. The heel 18 provides lift on the centerboard side at high speeds.

The sailboat 10 is movable by a pair of bridles 76, 78 which are attached to each side of the wing sail at the forward and aft ends of the bottom frame 54. The sailboat 1o is preferably "sailed" with the operator in a standing position partially supported by a swing 81, as shown in FIG. It requires sailing and pitching at a constant angle of attack of 10° and that the wing set 16 is oriented at the appropriate angle to the apparent wind. ), and can sail in either direction.When the sailboat 10 is held horizontally as shown in FIG. 8, it sails straight.

When a sailing ship rolls to one side, the center of lift of the wing set moves further toward that side than the center of drag of the hydrofoil 12.14, causing the sailing ship to roll (in the rolling direction). At sailboat speeds above 8.5 knots, a roll to windward will bring the sailboat away from the wind, and a roll to leeward will cause the sailboat to roll away from the wind. The sailboat is brought against the wind.One hull tube is approximately 8
．． When the sailboat is underwater below 5 knots, the roll control operation is reversed. A roll to windward brings the sailing vessel lO against the wind, and a roll to leeward brings the sailing ship away from the wind. By manipulating the reins 76,78, the operator can change the direction of the wing set 16. Furthermore, when the direction of sailboat 10 is reversed, the operator can reverse the asymmetric shape of the wing set from one side to the other. The direction of the sailboat 10 is most easily reversed when the sailboat's course is made perpendicular to the true wind, and the wing set 16 is feathered to slow the sailboat's forward motion.
be done. At this time, the operator releases the wing set control reins 76, 78 on one side of the wing set 16, moves it to the opposite end of the sailboat, picks up the control reins on the other side of the wing set, and reverses the asymmetric shape of the wing set. Pull the reins taut to sail in the opposite direction. When sailboat 10 is traveling in one direction, hydrofoil 12 is a bow hydrofoil and hydrofoil 14 is a stern hydrofoil. When the sailing vessel 10 is moving in the opposite direction, the hydrofoil 14
is the bow hydrofoil, and hydrofoil 12 is the stern hydrofoil.

Since the mast 50 freely rotates within the bracket 42,
The operator can easily change the direction of the wing set 16.

Additionally, the operator can reverse the asymmetry of the airfoil set 16 and change the pressure and suction sides of the airfoil set by changing the relative position of the forward section 56 and aft section 58 of the bottom frame 54. can.

Another practical example of the present invention is from a powered hydrofoil boat, which has a high aspect ratio at the bow and stern, and a water-piercing hydrofoil 12 having an inverted arch shape as shown in FIG.
．． It has 14. Means are provided for interconnecting the bow and stern hydrofoils similar to the means shown in Figure 1.2. Alternatively, drive means may be provided on the hydrofoil to propel the boat equally well in the fore-and-aft direction.

The present invention is susceptible to changes without departing from the scope of the invention, and the above description is given by way of example only, and the present invention is not intended to be driven by them.

[Brief explanation of the drawing]

Figure 1 is a top view of the hydrofoil sailboat of the present invention; Figure 2 is a side view of the sailboat of Figure 1; Figure 3 is a front view of the sailboat of Figure 1; Figure 4 is the sailboat of Figure 1. A perspective view of the bottom frame of the bipartite structure of the wing set; FIG. 5 is a section m1 taken along line 5--5 of FIG. IO... Underwater sailing ship, 12... Bow hydrofoil, 14.
...Stern underwater g, 16...wing set, 18...heel,
20... Tip plate, 22.24... Hull abduction or tube,
26...End cap, 28.30...Deck board, 8
2...Frame, 8.4. d6, 38.40...Tension material, 44...Deck, 50...Mast, 54...
・Bottom frame, 56...Front section, 58...
Rear section, 60... every Irsock, 62...
Tongue piece, 64...excision section. 67... Dark rear surface, 70... Lower spar wing end plate, 76
゜78... hand net.

Claims (1)

[Scope of Claims] L The following configurations (a) to (C): (a) High aspect ratio hydrofoils at the bow and stern, each having an inverted arch shape; (b) Front [ means for interconnecting hydrofoils; (C) sail means disposed on said interconnecting means, said sail means being free to rotate relative to said interconnecting means; Hydrofoil sailing boat. 2. In the hydrofoil sailing boat according to claim 1, each of the bow and stern hydrofoils has a substantially arcuate cross section, and the cross-sectional area and chord length of each hydrofoil are equal to the hydrofoil length. A hydrofoil sailing ship that is characterized by increasing in size from the center to both ends. & A hydrofoil sailing boat according to claim 1, wherein each of the bow and stern hydrofoils includes a pair of heels provided on the bottom surface thereof. 4- In the hydrofoil sailing vessel according to claim 1, the sailing vessel is a blower, and the sail means has the following configurations (a) to (e), namely: (a) the interconnection means; a mast supported in a cantilevered manner and inclined at an angle of 15° to 45° thereto; ('b) an upper frame supported by said mast;
<C) an articulated lower frame mounted on said mast and restrained for pivoting movement relative thereto; (d) a sail sock strung between said upper frame and lower frame; (e) said mast A hydrofoil sailing vessel, characterized in that the upper frame is rotatably mounted on interconnection means, and the upper frame is rigidly fixed against movement relative to the mast. & A hydrofoil sailing vessel according to claim 4, wherein the articulated lower frame includes a forward section and an aft section, and at least one of the sections is pivotally mounted on the mast. A hydrofoil sailing ship featuring aBf! j In the hydrofoil sailing ship according to claim 5,
the sail sock is secured to the upper frame and to the aft section of the lower frame, the forward section of the lower frame being in contact with and having limited movement relative to the sail sock; A hydrofoil sailing vessel characterized by being restrained. 7. The hydrofoil sailing vessel according to claim 1, wherein the sail means is a wing sail defining an asymmetric wing body and having means for reversing the asymmetric shape; When the changing means is in a first position, one side of the sail forms a pressure side and the opposite side of the sail forms a suction side, and when the shape changing means is in a second position, the - A hydrofoil sailing vessel characterized in that the side forms a suction side and the side opposite the wing sail forms a pressure side. & Configurations of the following (a) to Cfi: (a) buoyancy means; (b) rotatable mast provided on the buoyancy means;
(0) an upper frame disposed at the upper end of said mast and movably fixed thereto; ((1) an articulated lower frame disposed at the lower end of said mast; Ce) said upper and lower frames; (f) said articulated lower frame is adapted to move relative to said mast, said sailsock means being disposed between said frames and said sailsock means defining said wing body; A sailing boat characterized in that the outer shape of is defined by the position of the lower frame with respect to the upper frame. 9. The sailing vessel of claim 8, wherein the lower frame includes a forward section and an aft section, each of the forward section and the aft section having limited pivoting movement relative to the mast. A sailing vessel characterized in that the position of the forward section relative to the aft section controls the profile of the wing body. 1. The sailing vessel of claim 9, wherein said sailsock is fixed to said upper frame and to said aft section of said lower frame, said forward section of said lower frame being in contact with said sailsock and A sailing vessel, characterized in that the sailing vessel is restrained to have limited movement relative to said sailsock. IL A sailing boat according to claim number, characterized in that rolling of the boat about its longitudinal axis changes the direction of travel of the boat. In the sailing ship according to claim II, when the ship rolls in one direction, the center of aerodynamic lift of the ship moves in that direction more than the movement of the center of hydrodynamic drag of the ship. A sailing ship that is characterized by its ability to move. 1 & The following configurations (a) to (e), namely: (a) water-piercing hydrofoils of high aspect ratio bow and stern having an inverted arch shape; (b) means for interconnecting said hydrofoils; (C)
A hydrofoil boat, comprising: drive means provided on the hydrofoil boat for propelling the boat in bow and stern directions.