US 3456609 A
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6 Sheets-Sheet l Filed July 26, 1967 BOP 9 Q mm 9 rm m? m? 0-. mm mm mm R mm mm Q 9 wv Q @N @m INVENTOR PETER 77/0/7195 Ms-wci /Vorr BY ovvw ATTORNEYS July 22, 1969 P. T. M. NOTT HYDROFOIL WATERCRAFT 6 Sheets-Sheet 3 Filed July 26, 1967 INVENTOR PETER 77 afim/fl-wc' 4 0 ATTORNEY July 22, 1969 P. T. M. NOTT HYDROFOIL WATERCRAFT 6 Sheets-Sheet 5 Filed July 26, 1967 K Fl INVENTOR PE TER HO/1195 /VCE lVarr ATTORNEY July 22, 1969 P. T. M. NOTT HYDROFOIL WATERCRAFT 6 Sheets-Sheet 4 Filed July 26, 1967 INVENTOR ETER 77/0/10; Hmcz A/o r ATTORNEY July 22, 1969 P. T. M. NOTT HYDROFOIL WATERCRAFT 6 Sheets-Sheet 6 Filed July 26, 1967 INVENTOR Prk 7710/1/95 lfzfWCi A/orr ATTORNEY United States Patent HYDROFOIL WATERCRAFT Peter Thomas Mence Nott, Smallfields, Mill Road,
Stock, Essex, England V Filed July 26, 1967, Ser. No. 656,176 Int. C1. 1563]) 1/30; B6311 25/00, 21/26 US. Cl. 11466.5 6 Claims ABSTRACT OF THE DISCLOSURE A hydrofoil watercraft having a forward and an aft hydrofoil. Variations in load on the forward hydrofoil cause it to pivot against a spring and alter the angle of incidence of the hydrofoil to minimize pitching. The forward hydrofoil includes two blades. The forward and aft hydrofoils are retractable and the forward hydrofoil is pivotal to effect steering.
This invention relates to hydrofoil watercraft. It is an object of the invention to provide a hydrofoil watercraft having automatic control of pitching movements. It is a further object to provide retractable hydrofoils to permit easy storage and transport.
According to the invention, a hydrofoil watercraft comprises a hull, a power unit for driving the craft through the water, and rear andforward hydrofoils mounted on struts beneath the hull, one of said hydrofoils comprising two blades extending laterally and downwardly from a central yoke, said yoke being arranged to pivot about an axis transverse to the major axis of the craft to vary the angle of incidence of said one hydrofoil and resilient means for opposing angular movement of said one hydrofoil about said transverse axis. The craft has one rear and one forward hydrofoil, each mounted on a strut, said forward hydrofoil being of inverted V form and mounted on a pivot on said strut, the axis of the pivot being transverse to the major axis of the craft, resilient means being provided for opposing angular movement of said one forwardhydrofoil, and the strut of said forward hydrofoil is arranged to pivot about asubstantially vertical axis, said forward hydrofoil constituting the sole steering means of the craft and sole sustaining means for the forward end of the craft. The rear and forward struts being pivotally mounted on said hull and retractable, the steering means and the resilient means retracting with said forward strut.
sociated with said resilient means. The craft has atleast one seat for the operator, said seat having an emergency cutout device for the power unit, operable by removal of load from the seat. l 5
Embodiments of the invention will now be described with reference to the accompanying drawings, in which:
FIGURE 1 is a perspective view of a hydrofoil water craft, partly broken away,
FIGURE 2 is a sectional side elevation of a forward hydrofoil and associated structure,
FIGURE 3 is a front elevation of the hydrofoil shown in FIGURE 2,
FIGURE 4 is a side elevation of an alternative forward hydrofoil assembly,
FIGURE 5 is a front elevation of the hydrofoil shown in FIGURE 4, and,
FIGURE 6 is a side elevation partly sectioned, of a hydrofoil assembly mounted on a hull.
In one embodiment of the invention illustrated in FIG- URES 1, 2, 3, and 6 of the accompanying drawings, a hydrofoil watercraft has a hull 10 having rearwardly extending portions of the sides of the hull 10a and 10b and a recessed transom indicated at 11 to accommodate an outboard power unit 12. A rear hydrofoil 13 is mounted be- Preferably, the forward hydrofoil has damping means as- See neath the hull 10, forward of the outboard power unit 12. Said rear hydrofoil 13 comprises a strut 14 of wedge cross section, having a sharp leading edge. An anticavitation plate 15 is mounted at the end of strut 14 just below the water line when the craft is supported by the hydrofoils. Below the plate 15, there is a strut 14a having a hydrofoil cross section. At the lower extremity of the strut 14a is mounted a substantially horizontal hydrofoil 16. At the forward end of the hull 10, a second hydrofoil 17 extends beneath the hull, said second hydrofoil 17 comprising two blades 18 and 19 extending downwardly and outwardly from a yoke 20, said yoke 20 being mounted by means of a pin 21 on a member 22 so as to be pivotable about an axis transverse to the major axis of the craft. The member 22 is integral with the lower end of a tubular column 23, which is inclined rearwardly so that its upper end is somewhat to the rear of its lower end. t
The column 23 extends upwardly through a sleeve 2 said sleeve 24 having bearing bushes 24a and-24b at its upper and lower ends. At the upper end of the column 23 is a bracket 25 having handlebars 26 for guiding the craft. An automobile pattern hydraulic lever damper 27 is mounted on the bracket 25 and has a lever arm 28 extending laterally from a shaft 29 of the damper 27, said lever arm 28 having at its free end, a pivot pin 30 to which is attached one end of a coil spring 31. The other end of the coil spring 31 is attached to an eyebolt 32 fixed to a lug 33 on the bracket 25. A rod 34 extends through the tubular column 23, and is pivotally connected by a pin 35 at its lower end to the yoke 20 and at its upper end is connected to the pin 30 on the arm 28 of the hydraulic damper 27. The diameter of the rod 34 is smaller than the internal diameter of the tubular column 23 to allow the rod to follow the arcuate paths of the lower pivot 35 and the upper pivot pin 30 during axial displacement of said rod 34.
The hull 10 has on the upper surface of the forward end, a casing 36 (see FIGURES 1 and 6) comprising a horizontal flat portion 36a and a rearwardly inclined pyramidal portion 36b. The casing 36 is stiffened by means of internal ribs 36c and is adapted to carry the sleeve 24 within the rearwardly inclined pyramidal portion 36b so that the axes of the pyramidal portion 36b and the sleeve 24 are substantially parallel. The casing 36 is mounted on the hull 10 by means of pins 37 near the forward edge of said horizontal flat portion 36a so as to allow said casing 36 to pivot between a first extreme position illustrated in FIGURES 1 and 6 and a second extreme position (not illustrated). The underside of the hull 10 has a recess 38 formed therein to accommodate the forward hydrofoil 17 in said second extreme position of the casing 36. The hull 10 is provided with fastening means 39 having a hook 40 which cooperates with a pin 41 on the sleeve 24 to retain the casing 36 is said first extreme position.
The hull 10 has a seat 42 mounted thereon for the operator of the craft. The seat 42 has emergency cutout means for the power unit 12, incorporated in the support 43, operable by removal of the weight of the operator from the seat 42.
In a second embodiment of the invention, illustrated in FIGURES l, 4 and 5, a hydrofoil watercraft is, with the exception of the forward hydrofoil assembly generally similar to the craft described in the first embodiment. Said forward hydrofoil assembly comprises a hydrofoil 17 of inverted V form as hereinbefore described, said hydrofoil being pivotally mounted on a member 22 by a pin 21. The member 22 is integral with the lower end of a tubular column 23, which is inclined rearwardly so that its upper end is somewhat to the rear of its lower end.
The column 23 is carried in a sleeve 24, having bearing bushes 24a and 24b at its upper and lower ends. The
sleeve 24 is fixedly mounted in the pivotable casing 36. At the upper end of the tubular column 23 is a bracket 44, which carries the handlebars 26 and has an arm 45 near its upper end, said arm having a pivot pin 46 at substantially its mid point and an eye 47 formed in the free end of said arm 45. A tie wire '48 is connected at its upper end to said eye 47 and at its lower end to an eyebolt 49 secured to a bracket 50, the bracket 50 being releasably attached to the hull 10. A telescopic hydraulic damper 51 has a coaxially mounted coil spring 52, the damper 51 is pivotally mounted at its upper end on the arm 45 by the pivot pin 46 and has a rod 53 mounted at its lower end. Said rod 53 extends through the tubular column 23 and is pivotally connected at its lower end to the yoke 20 of the hydrofoil 17 by the pivot 35.
In operation, when the craft has attained sufficient forward speed, the lift from the hydrofoils is sufficient to overcome the weight of the craft and lift the hull clear of the surface of the water. When the craft is supported on the hydrofoils, variation in load on the forward hydrofoil, such as a wave, cause the hydrofoil to deflect against the resilient means and reduce the angle of incidence, thus reducing lift and reducing the tendency for the front of the craft to follow the Wave.
As the forward hydrofoil is load actuated, wide differences in weight between different operators may modify the stabilising characteristics of the forward hydrofoil, and adjustment means may be provided for varying the tension exerted by the resilient means.
1. A hydrofoil watercraft comprising in combination:
a floatable hull;
a rear hydrofoil mounted beneath the hull;
a forward hydrofoil;
a mounting assembly for said forward hydrofoil, said mounting assembly including a forward strut axially rotatably but lengthwise fixed to the hull and supporting said hydrofoil pivotal about an axis transverse of the lengthwise axis of the hull for respectively steering the craft by rotating said forward strut and hydrofoil and automatically varying the angle of incidence of the forward hydrofoil in response to the hydraulic pressure acting thereupon;
an elongate control member lengthwise displaceable in reference to said forward strut and hinged on one end by a hinge means to said forward hydrofoil at a point thereof spaced apart from its pivot axis; and
damping means yieldably resisting pivotal movements of the forward hydrofoil.
2. A hydrofoil watercraft comprising a hull, a power unit for driving the craft through the water and one rear and one forward hydrofoil mounted on struts beneath the craft, said forward hydrofoil being pivotally mounted on one of said struts, the axis of the pivot being transverse to the major axis of the craft, said one strut being rotatable and constituting, with said forward hydrofoil, the sole steering means of the craft and the sole supporting means for the front of the craft, said forward strut being pivotally mounted on said hull and retractable, the forward hydrofoil retracting with said forward strut.
3. A hydrofoil water craft according to claim 1 wherein said forward strut comprises a tubular member mounting on one end a yoke pivotally supporting said forward hydrofoil, and said control member comprises a rod lengthwise displaceable within said tubular member; and wherein said damping means comprises a spring means secured at one end to said rod and at the other end to a point spatially stationary in reference to said tubular member.
4. A hydrofoil watercraft according to claim 3 wherein the inner cross sectional area of said tubular member is larger than the maximal cross sectional area of the rod portion within the tubular member so as to provide clearance permitting the rod to follow accurate movements of the hinge means joining the rod to the forward hydrofoil when the latter performs a pivotal movement.
' 5. A hydrofoil watercraft according to claim 1 and further comprising a power drive means secured to the hull at the stern thereof for driving the craft in substantially linear direction, said forward hydrofoil and strut supporting the same constituting the sole steering means of the craft; weight controlled fail-safe cutout means for the drive means; and at least one seat on the hull for the operator of the craft, said out out means being spatially associated with said seat so that the hinge means is rendered ineffective while and when the seat is loaded by the weight of the operator or a comparable weight.
6. A hydrofoil watercraft comprising:
a power unit for driving the craft through the water;
a rear hydrofoil mounted beneath the hull;
a forward strut protruding beneath the hull, said strut being mounted rotatable with reference to the hull and retracting into the hull;
a forward hydrofoil supported on said strut for rotation and retraction in unison with the same, said strut and said forward hydrofoil constituting the sole steering means of the craft and the sole supporting means for the bow part of the craft when the same is driven through the water as a hydrofoil craft.
References Cited UNITED STATES PATENTS 2,612,232 9/1952 Morrison 200 2,955,559 10/1960 Palmer et al 114-665 ,141,437 7/1964 Bush et al. 114-665 3,369,513 2/1968 Nott 114-665 ANDREW H. FARRELL, Primary Examiner