US3773011A - Propulsion fin for a floating body - Google Patents

Propulsion fin for a floating body Download PDF

Info

Publication number
US3773011A
US3773011A US00227524A US3773011DA US3773011A US 3773011 A US3773011 A US 3773011A US 00227524 A US00227524 A US 00227524A US 3773011D A US3773011D A US 3773011DA US 3773011 A US3773011 A US 3773011A
Authority
US
United States
Prior art keywords
diaphragm
frame
fin
floating body
propulsion
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
US00227524A
Inventor
J Gronier
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Individual
Original Assignee
Individual
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Individual filed Critical Individual
Application granted granted Critical
Publication of US3773011A publication Critical patent/US3773011A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • BPERFORMING OPERATIONS; TRANSPORTING
    • B63SHIPS OR OTHER WATERBORNE VESSELS; RELATED EQUIPMENT
    • B63HMARINE PROPULSION OR STEERING
    • B63H1/00Propulsive elements directly acting on water
    • B63H1/30Propulsive elements directly acting on water of non-rotary type
    • B63H1/36Propulsive elements directly acting on water of non-rotary type swinging sideways, e.g. fishtail type

Definitions

  • COWL FOR OUTBOARD MOTOR Cowls have been employed on outboard motors to protect the engine from the elements and the boat occupants from any contact with the engine.
  • cowls have previously been employed.
  • the previously available cowls have been mounted on the engine so that access to a portion of the engine is blocked by a portion of the cowl after the readily removable portions of the cow] have been removed.
  • the previously available cowls have necessitated further disassembly of the outboard motor beyond mere removal of the cow] for one to have access to any portion of the engine.
  • cowls had to be partially removed to permit access to make adjustments to the carburetor.
  • partial disassembly of the cowl has previously been necessary to make adjustments to adjustable elemtns such as the carburetor idle, which are located on the front of the engine.
  • the present invention satisfactorily overcomes the foregoing problems by providing a cowl which is formed so that all portions of the engine are accessible when the cowl is removed. There is no'requirement for any further dissassembly of the engine from the driveshaft housing as with the previously available cowls.
  • the unique configuration of the cowl of the present invention also enables one to be able to make adjustments to any of the adjustable elements on the front of the engine without having to remove the complete cowl. It is only necessary to remove a releasable front shield or cover.
  • An object of this invention is to provide an improved cowl for an outboard motor.
  • Another object of this invention is to provide a cowl for an outboard motor in which all the parts of the cowl can be quickly and easily removed.
  • This invention relates to an outboard motor including a driveshaft housing, an engine supported on the driveshaft housing, and a cowl surroundingtheengine.
  • the cowl comprises a pair of members connected to each other adjacent their rear ends with their front ends spaced from each other and releasably connected by suitable means.
  • the members are releasably supported on the engine by means to provide the sole support for the members directly on the engine.
  • This invention also relates to a cowl for surrounding an engine including first and second members surrounding portions of the engine and means to connect the rear ends of each of the first and second members to each other.
  • the members are releasably supported on the engine by means.
  • the members have their front ends spaced from each other to permit access to the front of the engine when the members are in surrounding relation to the engine with the spaced front ends of the members being releasably connected to each other vby suitable means.
  • FIG. 3 is a front elevational view, similar to FIG. 1, but showing a front cover or shield removed;
  • FIG. 4 is a rear elevational view of a portion of the cowl as viewed from the inside of the cowl and showing the hinged relation of the members of the cowl to the rear bracket of the cowl;
  • FIG. 5 is a side elevational view of one of the two members of the cowl
  • FIG. 6 is a rear elevational view of a rear frame of the support assembly for the cowl
  • FIG. 7 is a sectional view taken along line 7-7 of FIG. 2 and showing the relation of portions of the members of the cowl to the top bracket of the support as sembly for the cowl;
  • FIG. 8 is a sectional view taken along line 8-8 of FIG. 2 and showing the relation of portions of the members of the cowl to the top bracket of the support assembly for the cowl;
  • FIG. 9 is a top plan view of a front plate, its sealing relationship with portions of the members of the cowl, and the latching arrangement for the front shield or cover of the cowl;
  • FIG. 10 is an enlarged elevational view of a resilient element for securing the front portions of the members of the cowl to each other;
  • FIG. 11 is a sectional viewtaken along line l1ll of FIG. 4 and showingthe relationship of the members and the rear bracket of the cowl to each other when the cowl is in its enclosing position.
  • FIG. 2 there is shown an engine 10 of an outboard motor with the engine 10 supported on a driveshaft housing 11 (see FIG.-1). As shown in FIG. 1, theengine 10 is enclosed by a cow] assembly 12.
  • the cowl assembly 12 includes a pair of members 14 and 15, which form a clam shell. As shown in FIG. 5 for the member 14 (the members 14 and 15 are mirror images), each of the members 14 and 15 includes a main side portion 16, a rear portion 17, a top portion 18, a
  • cowl assembly 12 When the cowl assembly 12 is in its surrounding relation to the engine 10 as shown in FIG.
  • the rear portions 17 are releasably connected to the rear bracket 21 by hinge means.
  • the hinge means includes a pair of vertically spaced apertured ears 22 (see FIG. 5) on the member 14, a pair of vertically spaced apertured ears (not shown) on the member 15 but positioned the same as the ears 22 on the member 14, and a pair of vertically spaced hinge members 24 (see FIG. 4) on the rear bracket 21.
  • Each of the hinge members 24 includes a base 25, which is secured to the rear bracket 21 by bolts 26 and nuts 27.
  • Each ot the bases 25 has a pair of upper hollow loops 28 and a pair of lower hollow loops 29.
  • Each of the upper hollow loops 28 is vertically aligned with one of the lower hollow loops 29.
  • a hinge pin 30 extends between the aligned hollow loops 28 and 29.
  • Each of the hinge pins 30 has an opening therein to receive a bolt 31, which is passed through one of the apertured ears 22 on the member 14 or one of the apertured ears (not shown) on the member 15.
  • Each of the bolts 31 has nut 32 cooperating therewith.
  • each of the members 14 and 15 can pivot about the vertical axes of the hinge pins 30 to PAIENTED NOV 20 1915 3373011 SHEET 10F 4 SHEET 2 OF 4 PATENTEU Nov 2 0 ms PATENTED RUY 2 0 I973 SHEET 30F 4 FIG.
  • the present invention relates to a propulsion fin for a floating body, comprising a flat member which is intended to be coupled externally to the said body and which, when at rest, extends substantially in a plane parallel to the direction of forward movement of the said body, the said member moving with a propulsive action during the course of operation, for example when the said body is allowed to oscillate.
  • the present invention has for its object a propulsion fin for a floating body, characterized in that it comprises a diaphragm supported by a rigid frame which is intended to be coupled to the said body, the said frame extending laterally and towards the rear and being open at the rear in such manner that the rear edge of the said diaphragm is free, the said diaphragm being constructed and mounted so as to be elastically deformable and having, in the position of rest, a mean position on the frame in which it is stretched with a pre-determined tension, the said diaphragm being mounted angularly movable on the frame so as to be displaced, in operation, on each side of the said mean position, between two extreme positions at which the tension of the diaphragm is greater than the said pre-tension and in which the diaphragm is inflated in the form of a pocket and makes from the start of the frame, an angle with the said mean position.
  • the said floating body is preferably permittedto oscillate by pitching with a downward plunging movement towards the front and a tail-down movement towards the rear, the said frame and the said diaphragm extending in a position of rest in a substantally horizontal frame.
  • the fin according to the invention provides a substantial propulsive effect from the start, this being true both for the tail-down and nose-down positions, because the deformation to a pocket of the diaphragm assists the horizontal component of the forces in the direction of forward movement.
  • the fin makes it possible to obtain high forward speeds, and in particular speeds of the order of 4 to 6 km. per hour.
  • the fin may be of the caudal type and in this case, the frame has preferably the shape of a fork with two arms and a central coupling handle to the floating body, each arm having a main front portion leaving the handle and extending laterally and towards the rear, and a rear end portion substantially parallel to the direction of forward movement.
  • the fin may also be lateral, and in this case, a supporting means is associated with the frame and/or with the floating body and serves to stretch the diaphragm.
  • the present invention has also for its object a floating body provided with at least one fin such as previously described, this floating body being intended to be ridden by a user like a horse.
  • the floating body is characterized in that it has a generally domed shape similar to that of a quarter of an orange, with a rising central portion which is straddled by the user and two lower end portions intended to remain continouusly submerged during the course of the oscillations impressed on the floating body by the user in order to move the body for ward.
  • Such a shape of the floating body has proved to be particularly effective for propulsion.
  • the almost continuous submersion of the body, especially at the front and the rear, during the oscillations permits a stabilization of the centre of thrust of the body, to the advantage of the operation.
  • the floating body preferably comprises, at the bottom of its central portion, two long lateral profiles parallel to the direction of forward movement, forming foot-rests and having a function of guiding and stabilization.
  • FIG. 1 is a view of a caudal fin according to the invention, this fin being in the position of rest;
  • FIG. 2 is a view of this fin in cross-section, taken along the line IIII of FIG. 1;
  • FIG. 3 is a view of the said fin in cross-section, taken along the chain-dotted line III--III of FIG. 1;
  • FIG. 4 is a view similar to FIG. 1, but in which the fin occupies one of its positions in which it is inflated in the form of a pocket;
  • FIG. 5 is a view in cross-section taken along the line V-V of FIG. 4;
  • FIG. 6 is a view in cross-section taken along the chain-dotted line VIVI of FIG. 4;
  • FIG. 7 shows to a larger scale a pivotal mounting of the diaphragm on the frame
  • FIGS. 8, 9, l0 and 11 are views similar to FIG. 1, but which relate respectively to four alternative forms;
  • FIG. 12 shows a plan view of two lateral fins in the position of rest
  • FIG. 13 is a view in cross-section taken along the chain-dotted line XIIIXIII of FIG. 12, the fins being in the position inflated as a pocket;
  • FIG. 14 is a diagrammatic view in perspective of a floating body provided with fins according to the invention.
  • Each arm 12 or 13 has a main portion 15 which is inclined to one side and towards the rear, and a rear transverse portion 16 substantially parallel to the direction of forward movement. It will be noted that the frame 11 is open at the rear.
  • the diaphragm 10 is constructed and mounted in such manner as to be elastically deformable and has, when at rest, a mean position on the frame 10 in which it is stretched with a pre-determined tension.
  • FIGS. l5, l6, l7, l8, l9 and 20 illustrate various pha-
  • the diaphragm 10 is composed of two flexible lateral portions 17 and 18 and a central portion 19 formed by an elastic fabric.
  • the portions 17, 18 and 19 may be assembled together by any appropriate means, for example the portion 19 may be double and fixed by a seam at 20 to the portions 17 and 18.
  • the diaphragm 10 is mounted so as to be angularly movable on the frame 11.
  • the front edge of the diaphragm is made tubular at 21. (see FIG. 7) and is pivotally mounted with play on the frame 11 for a rotating movement of the diaphragm 10 at that place. It will be appreciated that the pivotal movement of the diaphragm 10 on the frame is carried out under excellent conditions, although the arms 12 and 13 are neither straight nor coaxial, due to the fact that the diaphragm 10 is deformable.
  • the diaphragm 10 moves, during operation, on each side of the meansposition between two extreme positions 10a and 10b (see FIG. 6) which are more or less distant from this mean position, depending on the tilting torque.
  • the tension of the diaphragm 10 is greater than the pre-tension in the mean position and the diaphragm is inflated in the form of a pocket (see in particular FIGS. and 6).
  • the diaphragm forms an angle A (FIGS. 5 and 6) with the mean position.
  • the rear edge of the diaphragm comprises a strip 22 free from any mounting on the frame 11 and forming a free flap.
  • the line L in chaindotted lines which separates the diaphragm proper from the flap 22.
  • the line L has a slightly elbowed general shape.
  • the section line III-III is substantially coincident with the line L.
  • the flap 22 forms an inflexion with the running portion of the diaphragm 10.
  • This flap 22 has the function of a trailing edge and ensures continuity of the streams of liquid by preventing a return of liquid towards the front.
  • the diaphragm 10 is advantageously made of a sheet material of constant thickness and is provided with stiffening ribs 23 parallel to the direction of forward movement.
  • the stiffening may be obtained by a gradual variation of the thickness of the diaphragm. It will be appreciated that the stiffening means by ribs 23 or the like extend on each side of the line L, which enables excellent continuity of the working profile to be obtained.
  • the fin such as this has been described with reference to FIGS. 1 to 7 is a caudal fin adapted to be arranged to the rear of a floating body.
  • the fin moves with a particularly effective propulsive action both for the tail-down and nose-down positions, enabling it to effect an immediate start and to obtain a high forward speed, in particular of the order of 4 to 6 km. per hour.
  • the diaphragm is com posed of two flexible portions 17 and 19 and an elastic portion 19, but the diaphragm may also be made uniformly elastic, as shown at 10 in FIG. 8.
  • the elastic fabric 10 may also be replaced, on the one hand by a system of elastic threads 19" coupling together the flexible portions 17 and 18, and on the other hand by a simple central closure portion 19",.
  • the diaphragm can be seen at 10'.
  • each arm 15 is substantially straight, but the arms may also be provided in an arcuate form at 15" as has been shown in FIG. 10.
  • the diaphragm can be seen at 10".
  • the diaphragm shown at 10 comprises a flexible nonextensible panel 24 articulated at 25 on a part of the frame 11, and coupled by elastic lacing 26 to another part of the frame.
  • FIGS. 12 and 13 in which the arrangement is similar to those which have just been described, but in which the fin is not a caudal but a lateral fin.
  • a supporting means 27 is preferably associated with the frame and/or with the floating body and serves to stretch the diaphragm.
  • each frame indicated by 111, receives an auxiliary rod 27 which extends along the floating body and which serves to stretch the diaphragm, designated by 110.
  • the fins are shown in the position of rest, and in FIG. 13 in the position inflated as a working pocket.
  • the lateral fins described with reference to FIGS. 12 and 13 also make it possible to obtain an effective propulsive effect.
  • FIG. 14 in which there is shown at 28 a floating body for a water sports game intended to be ridden astn'de by a user and having at the rear a caudal fin 10 such as that which has been described with reference to FIGS. 1 to 7, and at the front two lateral fins such as those which have been described with reference to FIGS. 12 and 13.
  • the floating body 28 has a generally domed shape similar to that of a quarter of an orange with a raised central portion 29 which is straddled by the user, and two extreme portions 30 and 31 which are lower and are intended to remain continuously submerged during the course of the oscillations of the body 28. It will be understood that the body 28 is wider at the top than at the bottom.
  • the body 29 further comprises two long lateral profiled members 32 parallel to the direction of forward movement.
  • Each member 32 is composed of an upper portion 32a inclined downwards and towards the exterior, and a lower horizontal portion 32b.
  • the profiled members form, on the one hand guides for maintaining the direction of forward movement, and on the other hand they constitute foot-rests at 32b. It will be appreciated that the members 32 have a stabilizing effect against a pitching movement or pounding, and, by virtue of the length, enable the feet to be placed either towards the front or the rear or in the centre at the will of the user.
  • FIG. 15 a device in the position of rest, in which the fins 10 and 110 are flat and horizontal.
  • FIG. 16 the user begins a nose-down movement, of which the completion of travel is shown in FIG. 17.
  • FIGS. 18 and 19 the user leans back by a taildown movement and there is shown in FIG. 20 the device at the end of the tail-down movement and at the beginning of another nose-down operation.
  • front fins 110 could be replaced by rigid lateral ailerons froming simple stabilizers. These ailerons may be shaped in the form of a shovel and may be mounted with a slight dihedron to the horizontal.
  • a propulsion fin for a floating body comprising a rearwardly opening rigid forked frame, an elastically deformable diaphragm stretched across the frame under an initial tension to normally maintain the diaphragm in a flat median position substantially coplanar with the frame, said diaphragm being pivotably mounted on the frame to rotate relative to the frame to positions on each side of said median position in which an angle is formed by the diaphragm at its attachment with the frame relative to the plane of the frame and in which the diaphragm is outwardly bulged forming a pocket under tension greater than the initial tension.
  • said elastic portion comprises an elastic fabric fixed to said flexible portion.
  • a floating body provided with at least one propulsion fin as claimed in claim 2, to be ridden astride by a user, said body having a generally domed shaped similar to that of a quarter of an orange, with a raised central portion straddled by the user and two lower end portions to remain continuously submerged during the course of the oscillations imparted by the user to said floating body for the forward propulsion of said body.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Combustion & Propulsion (AREA)
  • Mechanical Engineering (AREA)
  • Ocean & Marine Engineering (AREA)
  • Toys (AREA)

Abstract

A propulsion fin for a floating body comprises a flat member adapted to be coupled externally to said body and extends, when at rest, in a plane substantially parallel to the direction of forward movement of said body, said member being intended to oscillate with a propulsive action during operation and comprising a diaphragm supported by a rigid frame coupled to said body, said frame extending laterally and towards the rear and being open at the rear so that the rear edge of the diaphragm is free, said diaphragm being constructed and mounted so as to be elastically deformable and having, when at rest, a mean position on said frame in which it is stretched with a pre-determined tension, and is mounted angularly movable on the frame in such manner as to move, during operation, from one side of said mean position to the other between two extreme positions in which the tension of the diaphragm is greater than said pre-tension, and in which the diaphragm is inflated in the form of a pocket and makes an angle with said mean position, starting from the frame. The invention is particularly applicable to floating bodies for water sports.

Description

COWL FOR OUTBOARD MOTOR Cowls have been employed on outboard motors to protect the engine from the elements and the boat occupants from any contact with the engine. Various types of cowls have previously been employed.
However, the previously available cowls have been mounted on the engine so that access to a portion of the engine is blocked by a portion of the cowl after the readily removable portions of the cow] have been removed. Thus, the previously available cowls have necessitated further disassembly of the outboard motor beyond mere removal of the cow] for one to have access to any portion of the engine.
Additionally, the previously available cowls had to be partially removed to permit access to make adjustments to the carburetor. Thus, partial disassembly of the cowl has previously been necessary to make adjustments to adjustable elemtns such as the carburetor idle, which are located on the front of the engine.
The present invention satisfactorily overcomes the foregoing problems by providing a cowl which is formed so that all portions of the engine are accessible when the cowl is removed. There is no'requirement for any further dissassembly of the engine from the driveshaft housing as with the previously available cowls. The unique configuration of the cowl of the present invention also enables one to be able to make adjustments to any of the adjustable elements on the front of the engine without having to remove the complete cowl. It is only necessary to remove a releasable front shield or cover.
An object of this invention is to provide an improved cowl for an outboard motor.
Another object of this invention is to provide a cowl for an outboard motor in which all the parts of the cowl can be quickly and easily removed.
Other objects of this invention will be readily perceived from the following description, claims, and
drawings.
This invention relates to an outboard motor including a driveshaft housing, an engine supported on the driveshaft housing, and a cowl surroundingtheengine. The cowl comprises a pair of members connected to each other adjacent their rear ends with their front ends spaced from each other and releasably connected by suitable means. The members are releasably supported on the engine by means to provide the sole support for the members directly on the engine.
This invention also relates to a cowl for surrounding an engine including first and second members surrounding portions of the engine and means to connect the rear ends of each of the first and second members to each other. The members are releasably supported on the engine by means. The membershave their front ends spaced from each other to permit access to the front of the engine when the members are in surrounding relation to the engine with the spaced front ends of the members being releasably connected to each other vby suitable means.
. outboard motor with which the cowl of the present invention is employed;
FIG. 3 is a front elevational view, similar to FIG. 1, but showing a front cover or shield removed;
FIG. 4 is a rear elevational view of a portion of the cowl as viewed from the inside of the cowl and showing the hinged relation of the members of the cowl to the rear bracket of the cowl;
FIG. 5 is a side elevational view of one of the two members of the cowl;
FIG. 6 is a rear elevational view of a rear frame of the support assembly for the cowl;
FIG. 7 is a sectional view taken along line 7-7 of FIG. 2 and showing the relation of portions of the members of the cowl to the top bracket of the support as sembly for the cowl;
FIG. 8 is a sectional view taken along line 8-8 of FIG. 2 and showing the relation of portions of the members of the cowl to the top bracket of the support assembly for the cowl;
FIG. 9 is a top plan view of a front plate, its sealing relationship with portions of the members of the cowl, and the latching arrangement for the front shield or cover of the cowl;
'7 FIG. 10 is an enlarged elevational view of a resilient element for securing the front portions of the members of the cowl to each other; and
FIG. 11 is a sectional viewtaken along line l1ll of FIG. 4 and showingthe relationship of the members and the rear bracket of the cowl to each other when the cowl is in its enclosing position.
Referring to the drawings and particularly FIG. 2, there is shown an engine 10 of an outboard motor with the engine 10 supported on a driveshaft housing 11 (see FIG.-1). As shown in FIG. 1, theengine 10 is enclosed by a cow] assembly 12.
The cowl assembly 12 includes a pair of members 14 and 15, which form a clam shell. As shown in FIG. 5 for the member 14 (the members 14 and 15 are mirror images), each of the members 14 and 15 includes a main side portion 16, a rear portion 17, a top portion 18, a
front portion 19, a lower portion 20, and a depending side portion 20. When the cowl assembly 12 is in its surrounding relation to the engine 10 as shown in FIG.
' 1, the rear portions 17 of the members 14 and 15 abut against oppositesides of a rear bracket 21 (see FIgS. 4 and 11).
The rear portions 17 are releasably connected to the rear bracket 21 by hinge means. The hinge means includes a pair of vertically spaced apertured ears 22 (see FIG. 5) on the member 14, a pair of vertically spaced apertured ears (not shown) on the member 15 but positioned the same as the ears 22 on the member 14, and a pair of vertically spaced hinge members 24 (see FIG. 4) on the rear bracket 21.
Each of the hinge members 24 includes a base 25, which is secured to the rear bracket 21 by bolts 26 and nuts 27. Each ot the bases 25 has a pair of upper hollow loops 28 and a pair of lower hollow loops 29.
Each of the upper hollow loops 28 is vertically aligned with one of the lower hollow loops 29. A hinge pin 30 extends between the aligned hollow loops 28 and 29. Each of the hinge pins 30 has an opening therein to receive a bolt 31, which is passed through one of the apertured ears 22 on the member 14 or one of the apertured ears (not shown) on the member 15. Each of the bolts 31 has nut 32 cooperating therewith.
Accordingly, each of the members 14 and 15 can pivot about the vertical axes of the hinge pins 30 to PAIENTED NOV 20 1915 3373011 SHEET 10F 4 SHEET 2 OF 4 PATENTEU Nov 2 0 ms PATENTED RUY 2 0 I973 SHEET 30F 4 FIG.
PAIENIEunuv20 ms 3713011 SHEET [1F 4 F/GM I l PROPULSION FIN FOR A FLOATING BODY The present invention relates to a propulsion fin for a floating body, comprising a flat member which is intended to be coupled externally to the said body and which, when at rest, extends substantially in a plane parallel to the direction of forward movement of the said body, the said member moving with a propulsive action during the course of operation, for example when the said body is allowed to oscillate.
A tin of this kind is described in French Pat. No. 1,322,642 of the present applicant and in the first Certificate of Addition No. 82,572 attached to this patent.
Interesting results can be obtained with theobject described in this French Patent and its Certificate of Addition, but in general starting-off is rather slow and the forward speed is fairly low. The applicant has made efforts in particular to improve the propulsion capacityv of the fin, and after numerous tests and researches, it has been found that considerably improved performances can be obtained when the fin consists of a deformable diaphragm elastically stretched over a rigid frame in such manner as to be capable of being inflated in the form of a pocket alternatively on one side or on the other.
The present invention has for its object a propulsion fin for a floating body, characterized in that it comprises a diaphragm supported by a rigid frame which is intended to be coupled to the said body, the said frame extending laterally and towards the rear and being open at the rear in such manner that the rear edge of the said diaphragm is free, the said diaphragm being constructed and mounted so as to be elastically deformable and having, in the position of rest, a mean position on the frame in which it is stretched with a pre-determined tension, the said diaphragm being mounted angularly movable on the frame so as to be displaced, in operation, on each side of the said mean position, between two extreme positions at which the tension of the diaphragm is greater than the said pre-tension and in which the diaphragm is inflated in the form of a pocket and makes from the start of the frame, an angle with the said mean position.
The said floating body is preferably permittedto oscillate by pitching with a downward plunging movement towards the front and a tail-down movement towards the rear, the said frame and the said diaphragm extending in a position of rest in a substantally horizontal frame.
The fin according to the invention provides a substantial propulsive effect from the start, this being true both for the tail-down and nose-down positions, because the deformation to a pocket of the diaphragm assists the horizontal component of the forces in the direction of forward movement. The fin makes it possible to obtain high forward speeds, and in particular speeds of the order of 4 to 6 km. per hour.
The fin may be of the caudal type and in this case, the frame has preferably the shape of a fork with two arms and a central coupling handle to the floating body, each arm having a main front portion leaving the handle and extending laterally and towards the rear, and a rear end portion substantially parallel to the direction of forward movement.
The fin may also be lateral, and in this case, a supporting means is associated with the frame and/or with the floating body and serves to stretch the diaphragm.
The present invention has also for its object a floating body provided with at least one fin such as previously described, this floating body being intended to be ridden by a user like a horse. The floating body is characterized in that it has a generally domed shape similar to that of a quarter of an orange, with a rising central portion which is straddled by the user and two lower end portions intended to remain continouusly submerged during the course of the oscillations impressed on the floating body by the user in order to move the body for ward.
Such a shape of the floating body has proved to be particularly effective for propulsion. In particular, the almost continuous submersion of the body, especially at the front and the rear, during the oscillations, permits a stabilization of the centre of thrust of the body, to the advantage of the operation.
The floating body preferably comprises, at the bottom of its central portion, two long lateral profiles parallel to the direction of forward movement, forming foot-rests and having a function of guiding and stabilization.
Forms of embodiment of the invention are described below by way of example, reference being made to the accompanying drawings, in which:
FIG. 1 is a view of a caudal fin according to the invention, this fin being in the position of rest;
FIG. 2 is a view of this fin in cross-section, taken along the line IIII of FIG. 1;
FIG. 3 is a view of the said fin in cross-section, taken along the chain-dotted line III--III of FIG. 1;
FIG. 4 is a view similar to FIG. 1, but in which the fin occupies one of its positions in which it is inflated in the form of a pocket;
FIG. 5 is a view in cross-section taken along the line V-V of FIG. 4;
FIG. 6 is a view in cross-section taken along the chain-dotted line VIVI of FIG. 4;
FIG. 7 shows to a larger scale a pivotal mounting of the diaphragm on the frame;
FIGS. 8, 9, l0 and 11 are views similar to FIG. 1, but which relate respectively to four alternative forms;
FIG. 12 shows a plan view of two lateral fins in the position of rest;
FIG. 13 is a view in cross-section taken along the chain-dotted line XIIIXIII of FIG. 12, the fins being in the position inflated as a pocket;
FIG. 14 is a diagrammatic view in perspective of a floating body provided with fins according to the invention;
. tral handle 14 for coupling to the floating body. Each arm 12 or 13 has a main portion 15 which is inclined to one side and towards the rear, and a rear transverse portion 16 substantially parallel to the direction of forward movement. It will be noted that the frame 11 is open at the rear.
The diaphragm 10 is constructed and mounted in such manner as to be elastically deformable and has, when at rest, a mean position on the frame 10 in which it is stretched with a pre-determined tension.
FIGS. l5, l6, l7, l8, l9 and 20 illustrate various pha- In the example shown in FIGS. 1 to 7, the diaphragm 10 is composed of two flexible lateral portions 17 and 18 and a central portion 19 formed by an elastic fabric. The portions 17, 18 and 19 may be assembled together by any appropriate means, for example the portion 19 may be double and fixed by a seam at 20 to the portions 17 and 18.
The diaphragm 10 is mounted so as to be angularly movable on the frame 11. For example, the front edge of the diaphragm is made tubular at 21. (see FIG. 7) and is pivotally mounted with play on the frame 11 for a rotating movement of the diaphragm 10 at that place. It will be appreciated that the pivotal movement of the diaphragm 10 on the frame is carried out under excellent conditions, although the arms 12 and 13 are neither straight nor coaxial, due to the fact that the diaphragm 10 is deformable.
With this arrangement, the diaphragm 10 moves, during operation, on each side of the meansposition between two extreme positions 10a and 10b (see FIG. 6) which are more or less distant from this mean position, depending on the tilting torque. In each extreme position, the tension of the diaphragm 10 is greater than the pre-tension in the mean position and the diaphragm is inflated in the form of a pocket (see in particular FIGS. and 6). In each extreme position, starting from the frame 11, the diaphragm forms an angle A (FIGS. 5 and 6) with the mean position.
It will be observed from FIG. 1 that the rear edge of the diaphragm comprises a strip 22 free from any mounting on the frame 11 and forming a free flap. There can be seen in FIGS. 1 and 4, the line L in chaindotted lines which separates the diaphragm proper from the flap 22. The line L has a slightly elbowed general shape. It will be noted from FIG. 1 that the section line III-III is substantially coincident with the line L.
It can be seen from FIG. 5 that in the extreme position of the diaphragm 10 inflated like a pocket, the flap 22 forms an inflexion with the running portion of the diaphragm 10. This flap 22 has the function of a trailing edge and ensures continuity of the streams of liquid by preventing a return of liquid towards the front.
It will also be noted from FIGS. 1 to 6 that the diaphragm 10 is advantageously made of a sheet material of constant thickness and is provided with stiffening ribs 23 parallel to the direction of forward movement. In an alternative form, the stiffening may be obtained by a gradual variation of the thickness of the diaphragm. It will be appreciated that the stiffening means by ribs 23 or the like extend on each side of the line L, which enables excellent continuity of the working profile to be obtained.
The fin, such as this has been described with reference to FIGS. 1 to 7 is a caudal fin adapted to be arranged to the rear of a floating body.
When this floating body is permitted to oscillate while pitching with a nose-down movement towards the front and a tail-down movement towards the rear, the fin moves with a particularly effective propulsive action both for the tail-down and nose-down positions, enabling it to effect an immediate start and to obtain a high forward speed, in particular of the order of 4 to 6 km. per hour.
In the example of FIGS. 1 to 7, the diaphragm is com posed of two flexible portions 17 and 19 and an elastic portion 19, but the diaphragm may also be made uniformly elastic, as shown at 10 in FIG. 8.
As shown in FIG. 9, the elastic fabric 10 may also be replaced, on the one hand by a system of elastic threads 19" coupling together the flexible portions 17 and 18, and on the other hand by a simple central closure portion 19",. The diaphragm can be seen at 10'.
In FIG. 1, each arm 15 is substantially straight, but the arms may also be provided in an arcuate form at 15" as has been shown in FIG. 10. The diaphragm can be seen at 10".
In another alternative form shown in FIG. 1 1, the diaphragm shown at 10", comprises a flexible nonextensible panel 24 articulated at 25 on a part of the frame 11, and coupled by elastic lacing 26 to another part of the frame.
Reference will now be made to FIGS. 12 and 13, in which the arrangement is similar to those which have just been described, but in which the fin is not a caudal but a lateral fin.
In the example of FIG. 12, two lateral fins are provided. A supporting means 27 is preferably associated with the frame and/or with the floating body and serves to stretch the diaphragm. For example, each frame, indicated by 111, receives an auxiliary rod 27 which extends along the floating body and which serves to stretch the diaphragm, designated by 110. In FIG. 12, the fins are shown in the position of rest, and in FIG. 13 in the position inflated as a working pocket.
The lateral fins described with reference to FIGS. 12 and 13 also make it possible to obtain an effective propulsive effect.
Reference will now be made to FIG. 14, in which there is shown at 28 a floating body for a water sports game intended to be ridden astn'de by a user and having at the rear a caudal fin 10 such as that which has been described with reference to FIGS. 1 to 7, and at the front two lateral fins such as those which have been described with reference to FIGS. 12 and 13.
The floating body 28 has a generally domed shape similar to that of a quarter of an orange with a raised central portion 29 which is straddled by the user, and two extreme portions 30 and 31 which are lower and are intended to remain continuously submerged during the course of the oscillations of the body 28. It will be understood that the body 28 is wider at the top than at the bottom.
At the bottom of its central protion, the body 29 further comprises two long lateral profiled members 32 parallel to the direction of forward movement. Each member 32 is composed of an upper portion 32a inclined downwards and towards the exterior, and a lower horizontal portion 32b. The profiled members form, on the one hand guides for maintaining the direction of forward movement, and on the other hand they constitute foot-rests at 32b. It will be appreciated that the members 32 have a stabilizing effect against a pitching movement or pounding, and, by virtue of the length, enable the feet to be placed either towards the front or the rear or in the centre at the will of the user.
There can be seen in FIG. 15 a device in the position of rest, in which the fins 10 and 110 are flat and horizontal.
In FIG. 16, the user begins a nose-down movement, of which the completion of travel is shown in FIG. 17.
In FIGS. 18 and 19, the user leans back by a taildown movement and there is shown in FIG. 20 the device at the end of the tail-down movement and at the beginning of another nose-down operation.
There will be observed from'FIGS. 16 to 20 the inflated shapes in the form of a pocket taken by the fins and 110.
It will be understood that the improved qualities of the floating body and the fins permit a harmonious equilibrium of the effort required from the user for the nose-down and tail-down movements, which both ensure a propulsive effect and may have substantially the same duration.
It will be noted that the front fins 110 could be replaced by rigid lateral ailerons froming simple stabilizers. These ailerons may be shaped in the form of a shovel and may be mounted with a slight dihedron to the horizontal.
What I claim is:
1. A propulsion fin for a floating body comprising a rearwardly opening rigid forked frame, an elastically deformable diaphragm stretched across the frame under an initial tension to normally maintain the diaphragm in a flat median position substantially coplanar with the frame, said diaphragm being pivotably mounted on the frame to rotate relative to the frame to positions on each side of said median position in which an angle is formed by the diaphragm at its attachment with the frame relative to the plane of the frame and in which the diaphragm is outwardly bulged forming a pocket under tension greater than the initial tension.
2. A propulsion fin as claimed in claim 1, in combination with a floating body on which the forked frame is secured.
3. A propulsion fin as claimed in claim 2, wherein the floating body is adapted to be pitched alternately nosedown towards the front and tail-down towards the rear causing the fin to oscillate to said positions thereby effecting forward movement.
4. A propulsion fin as claimed in claim 3, further comprising a strip disposed along the rear edge of the diaphragm and forming a free flap.
5. A propulsion fin as claimed in claim 3, in which the diaphragm is attached to the frame by a tubular sleeve.
6. A propulsion fin as claimed in claim 2, in which said diaphragm comprises at least one elastic portion allowing expansion thereof.
7. A propulsion fin as claimed in claim 6, in which the diaphragm also comprises at least one flexible portion.
8. A propulsion fin as claimed in claim 7, in which said elastic portion comprises an elastic fabric fixed to said flexible portion.
9. A propulsion fin as claimed in claim 7, in which said elastic portion comprises at least one elastic thread connection.
10. A propulsion fin as claimed in claim 6, in which a panel of the diaphragm is pivotally mounted on one portion of said frame and coupled by elastic lacing to another portion of said frame.
11. A propulsion fin as claimed in claim 6, in which said diaphragm is entirely elastic.
12. A propulsion finas claimed in claim 2, in which said fin is of the caudal type in which the forked frame is joined to a central shaft for securing the frame to said floating body and in which each branch of the fork has a main portion extending from the shaft laterally and rearwardly and a rear projecting terminal portion substantially parallel to the longitudinal axis of the floating body.
13. A propulsion fin as claimed in claim 12, in which said main portion is substantially linear.
14. A propulsion fin as claimed in claim 12, in which said main portion is curved.
15. A propulsion fin as claimed in claim 1, in which said fin is of the lateral type, and in which supporting means is associated with said frame for stretching said diaphragm.
16. A propulsion fin as claimed in claim 2, in which said fin is of the lateral type and further comprising a supporting means associated with said floating body and adapted to stretch said diaphragm.
17. A floating body provided with at least one propulsion fin as claimed in claim 2, to be ridden astride by a user, said body having a generally domed shaped similar to that of a quarter of an orange, with a raised central portion straddled by the user and two lower end portions to remain continuously submerged during the course of the oscillations imparted by the user to said floating body for the forward propulsion of said body.
18. A floating body as claimed in claim 17, and further comprising, at the bottom of its central portion, two long lateral profiled members parallel to the longitudinal axis of floating body providing footrests and guiding and stabilizing said body.

Claims (18)

1. A propulsion fin for a floating body comprising a rearwardly opening rigid forked frame, an elastically deformable diaphragm stretched across the frame under an initial tension to normally maintain the diaphragm in a flat median position substantially coplanar with the frame, said diaphragm being pivotably mounted on the frame to rotate relative to the frame to positions on each side of said median position in which an angle is formed by the diaphragm at its attachment with the frame relative to the plane of the frame and in which the diaphragm is outwardly bulged forming a pocket under tension greater than the initial tension.
2. A propulsion fin as claimed in claim 1, in combination with a floating body on which the forked frame is secured.
3. A propulsion fin as claimed in claim 2, wherein the floating body is adapted to be pitched alternately nose-down towards the front and tail-down towards the rear causing the fin to oscillate to said positions thereby effecting forward movement.
4. A propulsion fin as claimed in claim 3, further comprising a strip disposed along the rear edge of the diaphragm and forming a free flap.
5. A propulsion fin as claimed in claim 3, in which the diaphragm is attached to the frame by a tubular sleeve.
6. A propulsion fin as claimed in claim 2, in which said diaphragm comprises at least one elastic portion allowing expansion thereof.
7. A propulsion fin as claimed in claim 6, in which the diaphragm also comprises at least one flexible portion.
8. A propulsion fin as claimed in claim 7, in which said elastic portion comprises an elastic fabric fixed to said flexible portion.
9. A propulsion fin as claimed in claim 7, in which said elastic portion comprises at least one elastic thread connection.
10. A propulsion fin as claimed in claim 6, in which a panel of the diaphragm is pivotally mounted on one portion of said frame and coupled by elastic lacing to another portion of said frame.
11. A propulsion fin as claimed in claim 6, in which said diaphragm is entirely elastic.
12. A propulsion fin as claimed in claim 2, in which said fin is of the caudal type in which the forked frame is joined to a central shaft for securing the frame to said floating body and in which each branch of the fork has a main portion extending from the shaft laterally and rearwardly and a rear projecting terminal portion substantially parallel to the longitudinal axis of the floating body.
13. A propulsion fin as claimed in claim 12, in which said main portion is substantially linear.
14. A propulsion fin as claimed in claim 12, in which said main portion is curved.
15. A propulsion fin as claimed in claim 1, in which said fin is of the lateral type, and in which supporting means is associated with said frame for stretching said diaphragm.
16. A propulsion fin as claimed in claim 2, in which said fin is of the lateral type and further comprising a supporting means associated with said floating body and adapted to stretch said diaphragm.
17. A floating body provided with at least one propulsion fin as claimed in claim 2, to be ridden astride by a user, said body having a generally domed shaped similar to that of a quarter of an orange, with a raised central portion straddled by the user and two lower end portions to remain continuously submerged during the course of the oscillations imparted by the user to said floating body for the forward propulsion of said body.
18. A floating body as claimed in claim 17, and further comprising, at the bottom of its central portion, two long lateral profiled members parallel to the longitudinal axis of floating body providing footrests and guiding and stabilizing said body.
US00227524A 1971-03-08 1972-02-17 Propulsion fin for a floating body Expired - Lifetime US3773011A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
FR7107893A FR2128898A5 (en) 1971-03-08 1971-03-08

Publications (1)

Publication Number Publication Date
US3773011A true US3773011A (en) 1973-11-20

Family

ID=9073114

Family Applications (1)

Application Number Title Priority Date Filing Date
US00227524A Expired - Lifetime US3773011A (en) 1971-03-08 1972-02-17 Propulsion fin for a floating body

Country Status (3)

Country Link
US (1) US3773011A (en)
DE (1) DE2210102C3 (en)
FR (1) FR2128898A5 (en)

Cited By (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3845733A (en) * 1973-01-02 1974-11-05 R Jackman Boat propulsion means
US4214547A (en) * 1978-07-31 1980-07-29 Hetland Philip R Rider propelled boat
US4968273A (en) * 1987-06-30 1990-11-06 Adam Momot Water-borne vessel
US5746631A (en) * 1996-01-11 1998-05-05 Mccarthy; Peter T. High efficiency hydrofoil and swim fin designs
US6095879A (en) * 1998-05-14 2000-08-01 Mccarthy; Peter T. Methods for creating consistent large scale blade deflections
US20020025744A1 (en) * 1998-05-14 2002-02-28 Mccarthy Peter T. Methods for creating large scale focused blade deflections
US6371821B1 (en) 1996-01-11 2002-04-16 Nature's Wing Fin Designs, Llc High efficiency hydrofoil and swim fin designs
US6482059B2 (en) 1997-05-09 2002-11-19 Mccarthy Peter T. High efficiency hydrofoil and swim fin designs
US6884134B2 (en) 2002-07-19 2005-04-26 Mccarthy Peter T. High deflection hydrofoils and swim fins
CN103273486A (en) * 2013-05-17 2013-09-04 南京航空航天大学 Jellyfish imitation robot and control method thereof
RU2749820C2 (en) * 2019-11-26 2021-06-17 Федеральное государственное бюджетное образовательное учреждение высшего образования "Санкт-Петербургский государственный университет" (СПбГУ)" Active bilge watercraft motion stabilizer

Families Citing this family (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2425976A1 (en) * 1978-05-19 1979-12-14 Marjanovic Dragoljub Small boat propulsion equipment - has flexible fin partly split in lengthwise direction and joined to rigid edge with socket for handle
WO1995015882A1 (en) * 1993-12-06 1995-06-15 Rodolphe Proverbio Muscle-powered watercraft
DE19515114A1 (en) * 1994-11-02 1996-05-09 Erich Dr Ing Henker Fin propulsion for muscle-powered water craft
US9738362B2 (en) * 2015-07-22 2017-08-22 Hobie Cat Company Flow fin
CN113305850B (en) * 2021-06-15 2022-03-08 西南科技大学 Flexible robot and design method thereof

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR1059558A (en) * 1952-07-08 1954-03-25 Sports nautical gear
US2854787A (en) * 1956-03-19 1958-10-07 Paul E Oberg Self propelled toy fish
US3232608A (en) * 1964-02-05 1966-02-01 Vlacancich Giovanni Water sports toys
US3440994A (en) * 1966-11-08 1969-04-29 Thomas L Mcgowan Swimming appliance
US3605676A (en) * 1968-01-30 1971-09-20 Joachim Spangenberg Motorless water-borne vehicles

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2173415A (en) * 1938-03-31 1939-09-19 Roland C Hill Propelling mechanism

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR1059558A (en) * 1952-07-08 1954-03-25 Sports nautical gear
US2854787A (en) * 1956-03-19 1958-10-07 Paul E Oberg Self propelled toy fish
US3232608A (en) * 1964-02-05 1966-02-01 Vlacancich Giovanni Water sports toys
US3440994A (en) * 1966-11-08 1969-04-29 Thomas L Mcgowan Swimming appliance
US3605676A (en) * 1968-01-30 1971-09-20 Joachim Spangenberg Motorless water-borne vehicles

Cited By (32)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3845733A (en) * 1973-01-02 1974-11-05 R Jackman Boat propulsion means
US4214547A (en) * 1978-07-31 1980-07-29 Hetland Philip R Rider propelled boat
US4968273A (en) * 1987-06-30 1990-11-06 Adam Momot Water-borne vessel
US7101240B2 (en) 1996-01-11 2006-09-05 Mccarthy Peter T High efficiency hydrofoil and swim fin designs
EP0880379A1 (en) * 1996-01-11 1998-12-02 McCARTHY, Peter Thomas High efficiency hydrofoil and swim fin designs
US6050868A (en) * 1996-01-11 2000-04-18 Mccarthy; Peter T. High efficiency hydrofoil and swim fin designs
US6607411B1 (en) 1996-01-11 2003-08-19 Mccarthy Peter T. High efficiency hydrofoil and swim fin designs
US6146224A (en) * 1996-01-11 2000-11-14 Mccarthy; Peter T. High efficiency hydrofoil and swim fin designs
US6719599B2 (en) 1996-01-11 2004-04-13 Mccarthy Peter T. High efficiency hydrofoil and swim fin designs
US6371821B1 (en) 1996-01-11 2002-04-16 Nature's Wing Fin Designs, Llc High efficiency hydrofoil and swim fin designs
US5746631A (en) * 1996-01-11 1998-05-05 Mccarthy; Peter T. High efficiency hydrofoil and swim fin designs
US6497597B2 (en) 1996-01-11 2002-12-24 Mccarthy Peter T. High efficiency hydrofoil and swim fin designs
EP0880379A4 (en) * 1996-01-11 2003-04-02 Peter Thomas Mccarthy High efficiency hydrofoil and swim fin designs
US6585548B2 (en) 1996-01-11 2003-07-01 Mccarthy Peter T. High efficiency hydrofoil and swim fin designs
US6482059B2 (en) 1997-05-09 2002-11-19 Mccarthy Peter T. High efficiency hydrofoil and swim fin designs
US6712656B2 (en) 1998-05-14 2004-03-30 Mccarthy Peter T. Methods for creating consistent large scale blade deflections
US20080032574A1 (en) * 1998-05-14 2008-02-07 Amy L. Goldman Method for creating consistent large scale blade deflections
US20020025744A1 (en) * 1998-05-14 2002-02-28 Mccarthy Peter T. Methods for creating large scale focused blade deflections
US6843693B2 (en) 1998-05-14 2005-01-18 Mccarthy Peter T. Methods for creating large scale focused blade deflections
US7862395B2 (en) 1998-05-14 2011-01-04 Mccarthy Peter T Methods for creating consistent large scale blade deflections
US6918805B2 (en) 1998-05-14 2005-07-19 Mccarthy Peter T. Methods for creating consistent large scale blade deflections
US7018256B2 (en) 1998-05-14 2006-03-28 Mccarthy Peter T Methods for creating large scale focused blade deflections
US6095879A (en) * 1998-05-14 2000-08-01 Mccarthy; Peter T. Methods for creating consistent large scale blade deflections
US7581997B2 (en) 1998-05-14 2009-09-01 Mccarthy Peter T Method for creating consistent large scale blade deflections
US6413133B1 (en) 1998-05-14 2002-07-02 Mccarthy Peter T. Methods for creating consistent large scale blade deflections
US20080045095A1 (en) * 1998-05-14 2008-02-21 Mccarthy Peter T Methods for creating consistent large scale blade deflections
US7465205B2 (en) 1998-05-14 2008-12-16 Mccarthy Peter T Methods for creating consistent large scale blade deflections
US20070037459A1 (en) * 2002-07-19 2007-02-15 Mccarthy Peter T High deflection hydrofoils and swim fins
US7601041B2 (en) 2002-07-19 2009-10-13 Mccarthy Peter T High deflection hydrofoils and swim fins
US6884134B2 (en) 2002-07-19 2005-04-26 Mccarthy Peter T. High deflection hydrofoils and swim fins
CN103273486A (en) * 2013-05-17 2013-09-04 南京航空航天大学 Jellyfish imitation robot and control method thereof
RU2749820C2 (en) * 2019-11-26 2021-06-17 Федеральное государственное бюджетное образовательное учреждение высшего образования "Санкт-Петербургский государственный университет" (СПбГУ)" Active bilge watercraft motion stabilizer

Also Published As

Publication number Publication date
DE2210102C3 (en) 1982-01-07
FR2128898A5 (en) 1972-10-27
DE2210102B2 (en) 1981-05-07
DE2210102A1 (en) 1972-09-14

Similar Documents

Publication Publication Date Title
US3773011A (en) Propulsion fin for a floating body
US3369518A (en) Aquatic vehicle
US3528380A (en) Trimaran with sprung center hull section
US4496325A (en) Collapsible paddle boat
US4936802A (en) Swinging and propelling ship
US3269351A (en) Engine
US3401663A (en) Catamaran boat construction with center spray shield
US3294055A (en) Watercraft
US3094962A (en) Hydro plane
US3062167A (en) Trim attachment for power boats
US3340845A (en) Motorized water board
US3500784A (en) Surface craft
US4349340A (en) Man-propelled hydrofoil boat
US3718111A (en) Motorized aqua disc
JP2518879B2 (en) Outboard motor support device
US2653563A (en) Boom and rudder assembly
US3139055A (en) Water vehicle
US2045645A (en) Skim boat
US3397670A (en) Water craft
US4077077A (en) Stabilizer keel
US3394673A (en) Water ski scooter
US3207117A (en) Outboard motor steering assembly
US2286914A (en) Rowboat attachment
US3307566A (en) Folding soft top
US4464126A (en) Finboard exercising apparatus