CA2164010A1

CA2164010A1 - Surface effect boat

Info

Publication number: CA2164010A1
Application number: CA002164010A
Authority: CA
Inventors: Leszek Balas
Original assignee: Individual
Current assignee: Individual
Priority date: 1995-11-28
Filing date: 1995-11-28
Publication date: 1997-05-29

Abstract

This invention relates to a multisurface air propelled and air supported craft primarily intended for alternative use on water, ice, swampland and secondarily on solid terrain such as gravel roads, river banks and any other relatively flat surface including surface voids like trenches. The calamaran type of craft is supported partially or in full by pressurized air diverted under the craft from main air propulsion and by hydrodynamic lift created by a rigid inflatable pontoons. Directional control is provided by rudders located behind the propeller. Stopping is accomplished by a pair of independent drag brakes located inside each pontoon, while lateral control is achieved by a variable lift valve.

Description

SURFACE EFFECT BOAT

SUMMARY OF THE INVENTION
A primary problem with a conventional Hovercraft is an inherent lack of directional control in tight spots and conse~uently high mainle"ai ,ce as a result of ~ccidenlal damage. According to the invention, the surface effect boat (SEB) catar"aran hull cG",prises of a tubular frame with a composite deck, a pair of rigid inflatable ponloons, a shrouded propeller propulsion package, an air scoopextending into a planing seal, a front skirt and an aircushion .;I ,a" Iber comprised of the said front skirt, bottom of the deck, pontool ,s sides and the planing seal.
The rigid inflatable pOI ,loon means, the bottom of the inflatable cylindrical tube inco, porate inner rigid member placed between internal air tight bladder and ponloon external fabric.
A drag brake means, an assembly comprised of a housing containing a rod pushed by an ~chl~tor, said assembly located inside the pontoon and attached to the pontoon inner rigid member. The said drag brake means while engaged extending drag rod outside of the ponloon bottom to drag on ridden surface.
The variable lift valve means, the air scoop area can be changed thereby vary volume of pressurized air flowing under the craft.
The shrouded propeller propulsion package means, self contained assembly comprised of an engine driving propulsive propeller and supported by an UA~ shaped frame, a propeller enclosed by a aerodynamic shroud, a front protective screen attached to the leading edge of the shroud and a set of rudders attached to the trailing edge of the shroud and means to connect the airscoop.
The primary object of the invention is therefore to provide a new very stable and easily controllable vehicle called SEB. Another object of this invention is to partially support the SEB using air flow from thrust propeller to reduce water drag. Another object of this invention is to provide the SEB with apuncture and wear resistant inflatable hull having water planing capability.
Further object of this invention is to provide the SEB with a stopping, directional and lateral slide control capability.
Other objects and advantages will be apparent in the following detailed description, take in conjunction with the accompanying drawings, in which:
FIG.1 is a side elevation view of the SEB.
FIG.2 is a top view of the SEB.
FIG.3 is a sectional view taken on line 1-1 of FIG.2.
FIG.4 is a combination of a front elevation and a partial sectional view taken on line 3-3 of FIG.3.
FIG.5 is an enlarged sectional view through pontoon taken on line 3-3 of FIG.3.

Z16q~10 FIG.6 is a sectional view taken on line 2-2 of FIG.2.
FIG.7 is an another embodiment of FIG.6.
DESCRIPTION OF PREFERRED EMBODIMENTS
The SEB is primarily intend for use on water, however the vehicle can operate on any reasonably flat surfaces by means of lifting effect of the air cushion and low friction runners.
As shown on Fig.1 and Fig.2 the vehicle has a body comprised of a tubular frame 12 incor~.oralir,g a rigid deck 10, two side ponloons 14 attached by straps 13 to the frame 12, a propulsion package 40, an air scoop 28, a planing seal 26, a front skirt 22 and a driver console 25 with sleering 27. The rigid deck 10 has fabric extensions: front 21 and back 11 that seal the air cushion chamberfrom the top.
The air cushion chamber is confined by a front skirt 21, rigid deck 10 with extensions 21 and 11, a planing seal 26 and side pon~oons 14. The front skirt 22is attached to a front bumper tube 20 and pontoons by a strap 23. The planing seal 26 is preferably made of a thin elastic sheet of plastic and attached between pontoo,ls by a strap 46 and extended to flexible fabric 24 as shown on Fig. 3. The planing seal has large holes 26' cut on the outboard surfaoe that are covered from the inside by hinged elastic flap valve plate 62 having drainage holes 62'. The flap valve plate may preferably be made lighter then water to allow flotation when the planing seal is submerged. If the craft is not moving, water floods the planing seal compartment 24' and lifts the flap valve plate 62 opening large holes 26'. When the air cushion chamber is pressurized the SEB
is lifted and water quickly escapes through the large holes 26' allowing fast planing. At the end, the flap valve 62 closes large holes 26' to prevent exoessive air loss. Any residu~l water is then discharged through drain holes 62' cut in the bottom of the flap valve plate 62.
The air scoop 28' directs part of the air flow developed by the propeller 34 in to the planing seal coillpal l,nent 24'. Part of the cylindrical surface of the air scoop may be include a veritable lift valve 48. The valve may be pivoted at the rear bumper tube 18. A driver controlled ~ctu~tor 60 may rotate the variable lift valve in to position 48'. In this valve position less thrust air is supplied for lift and more for propulsive thrust. In effect more weight is supported by side pontoons improving overall directional control.
The pressurized air exits the planing seal compartment 24' via a check valve 43 rotaled between pontoons and along the line of strap 46 and supported at the exit end by a multitude of strings 47. The main function of the check valve 43 is to prevent large water ingestion into the planing seal cor~"~a, l",enl 24'during rapid slopp.ng or going over rough water. When large wave impacts, the valve rotate into position 43' closing momentarily planing seal compartment and preventing flooding.
The periphery of the air cushion chamber is comprised of a front skirt 21, pontoons runners 16 and the planing seal 26. The runner 16 is preferably made 3 ~16q~1~

of low friction wear resistant plastic sufficiently rigid to provide partial hydrodynamic lift at higher trim angles of the craft.
The main difference between side wall Hovercraft or surface effect ship and the SEB is that side walls of the Hovercraft are rigid and below skirt levelmaking the craft non amphibious while the SEB pontoon runners are flexible and at the skirt level allowing fully amphibious operation of the craft.
The rigid inflatable ponloon in embodiment shown on Fig.5 is cGmprised of a rigid runner insert 64 lo~le d between pontoon exter"al me"~brane 14 and internal air tight bl~1der 15 a runner wear pad 16 a puncture resistant skin 52 and spray deflectors 56. The wear pad 16 and the spray deflector 56 may be connected to the puncture resistant skin 52 by rivets 58. The puncture resislantskin 52 may be laced to the pontoon by lacing 54. The brake assembly 66 may be an integral part of the runner insert 64 that protrudes into the bladder 15 through pocket 15'.
Other embodiment of the rigid inflatable pontoon is shown on Fig.7. Here the runner insert 65 is lo~ted between pontoon exter"al membrane 14 and the puncture resistant skin 52. The brake assembly 66 may be an integral part of the runner insert 65 and be loc~ted between pontoon external fabric 14 and inner bladder 15 on the outho~rd side of the pontoon.
The brake assembly is comprised of inclined forwardly or both forwardly and oul~-o~rdly housing 66 an ~ch ~tor 70 and a drag rod 52. The ~c~u~tor is fixed to the housing by pin 74 and to the drag rod by pin 72. The drag rod may be guided on one end by per",anently attached to its surface guides 51 and on the other end by guides 53 that are attached to housing 66. When the ~ctu~tor is extended the drag rod is pushed outside pontoon to drag on ridden surface.
Any suitable type of control can be used to operate the various elements either mechanical electrical or fluid power.
From the foregoing it is believed that the invention may be readily understood by those skilled in the art without further description it being born in mind that numerous ~ ,anges may be made in the details disclosed without departing from the scope of the invention as set forth in the following claims.

Claims

1. A surface effect boat capable to operate over water, semi-solid and solid surfaces, comprising:
a vehicle hull having a tubular frame means, supporting a deck, a shrouded propeller power package, a pair of semi rigid inflatable pontoons, said pontoons means including laced external protective sheet of plastic, a front skirt, an air scoop, a planing seal means connecting the said air scoop with an air cushion chamber, a suitable steering system;
and a shrouded propeller power package means, a self standing propulsion unit having a frame, an engine driving a propeller, a protective screen, an aerodynamically shaped shroud, a set of driver operated rudders, and means to attach an air scoop; and a semi rigid inflatable pontoon means, the bottom of the pontoon incorporate suitably stiff member that may be placed between internal air bladder and external membrane or between external membrane and puncture resistant skin, the said member having integrally built in braking system; and an air scoop means, a flexible duct contoured to the propeller shroud exit and directing pressurized air from behind the propeller into a planing seal;
and a planing seal means, a flexible sheet of plastic stretched between pontoons conveying pressurized air from the air scoop into a plenum chamber; and an air cushion chamber means, a space enclosed by a front skirt, a planing seal, inboard sides of pontoons, a deck and ridden surface.

2. A surface effect boat according to claim 1, wherein said inflatable pontoons are additionally protected by laced sheet of plastic.

3. A surface effect boat according to claim 2, wherein said sheet of plastic is additionally protected in the area of direct contact with ridden surface by a replaceable runner pad.

4. A surface effect boat according to claim 2, wherein said sheet of plastic include antyspray guards on the inboard and outboard side of the pontoon, said guards projecting substantially radially and along the length of the pontoon.

5. A surface effect boat according to claim 1, wherein said integrally built in braking system has a housing including a drag rod inclined either forwardly of both forwardly and outboardly, and means to extend said drag road outside bottom of the runner pad.

6. A surface effect boat according to claim 1, wherein said air scoop includes pivotally mounted valve flap rotating toward the shroud for selective opening of portions of said air scoop to supply more propulsive thrust and less lift air for increased loading of runners.

7. A surface effect boat according to claim 1, wherein said planing seal means includes large holes cut on the outboard surface of the seal that are covered from the pressurized side of the seal by a hinged elastic flap valve plate having small drainage holes.

8. A surface effect boat according to claim 7, wherein said hinged elastic flap valve plate includes means to remotely open it by the driver.

9. A surface effect boat according to claim 1, wherein said planing seal means extends into a check valve plate that is rotated between pontoons and a common edge with the said planing seal and supported at the exit by a multitude of strings attached to the underside of the frame structure.