WO2013024195A1

WO2013024195A1 - Aquatic propulsion by means of oscillating fins

Info

Publication number: WO2013024195A1
Application number: PCT/ES2012/070626
Authority: WO
Inventors: José SAN GABINO RAMIREZ
Original assignee: San Gabino Ramirez Jose
Priority date: 2011-08-17
Filing date: 2012-08-14
Publication date: 2013-02-21
Also published as: ES2411554B1; EP2746147A1; EP2746147A4; US20140205453A1; WO2013024195A4; ES2411554A1

Abstract

The aquatic propulsion proposed uses oscillating blades (1, 2, 3, 4, 5) provided with independent, mutually parallel vertical shafts (9) affixed, at the upper end thereof, to a single horizontal oar (11) of planar profile, said blades or fins being of different length on the basis of the distance between the fastening point of the actual oscillation shaft thereof and the shaft (12a) on which the oar rocks. Propulsion is achieved when the user applies his/her muscle strength in traction or thrust on any of the two grips (16) provided at either end of the handlebars (14), or in opposite directions on both at one and the same time; said movement is transmitted to the rotary shaft (12a) and then to the profile section (11) on which the fins are arranged, which causes the fins to move transversely and alternately in both directions, thereby causing displacement of the water and, as a result, the propulsion of the swimmer or floating object or vehicle, in the intended direction, which corresponds to the intermediate point of the rocking travel of the oar (11).

Description

PERFECTED AQUATIC PROPULSION WITH HIGH PERFORMING OSCILLATING FINS

AMBITO TECNICOTECHNICAL FIELD

The invention relates to an aquatic propulsion with high-performance oscillating fins, particularly intended to propel small aquatic vehicles and surface floating objects, although it can also be applied as an underwater propellant for divers or underwater vehicles.

OBJETO DE LA INVENCIONOBJECT OF THE INVENTION

As can be seen from the title of the present specification, the object of the invention is to manufacture an aquatic propulsion using blades or oscillating fins transverse to the direction of advancement as the driving element of a vehicle or floating object; whose novel characteristics substantially reduce the travel of the surface of the blade in neutral and negative angle, producing smaller oscillations with respect to the longitudinal and transverse axis of the waterline because they facilitate the maximum approach of the propellant element, parallel to the lower plane of the vehicle, and to place the axis of rotation of the arm or rocking oar in front of the keels of the maneuvering axis, improving the effective hydrodynamic coefficient and obtaining a propelling efficiency far superior to that which had been achieved with these systems; but, in addition, allowing to vary the speed with drive frequencies and identical transverse travel; facilitating, in addition, the exchange of the fins in seconds, even in the water, in case of damage in an abrupt impact or to replace them with others that allow the adaptation of the propeller to the area in which the vehicle moves, either of greater height , to obtain a greater propulsion capacity, or with softer edges, to be used in the presence of other bathers.

Another object of the invention is to provide a simple, powerful and highly maneuverable muscular propulsion, suitable for use by children, the elderly or people with some type of disability.

ANTECEDENTES DE LA INVENCIONBACKGROUND OF THE INVENTION

The system of muscular propulsion known, more powerful and simple that exists to move in the aquatic environment, is unquestionably the one that uses oscillating fins, used by thousands of species of fish and marine animals in all seas, rivers and lakes around the world ; where the fastest reach speeds above 100 kilometers per hour. But the human being has been unable, to date, to obtain minimally acceptable propulsion coefficients, using alternative oscillating devices, provided with submerged fins, partially flexible or rigid, profiled vertically or horizontally with respect to the vehicle.

A classic oar, with perpendicular travel to the longitudinal waterline, can only obtain one-way propulsion, which means a useless loss, having to move out of the water to recover the initial position, the propulsion that is obtained varies proportionally depending on the angle, but always within positive parameters, with entry near the stern at minimum propulsion angle, in transit to the right angle where the propulsion is even, reducing again in the transit to the bow. The decrease in energy is greater the closer the paddle is to the line of progress; For this reason, increasingly longer oars are used that offer a greater distance close to the pair.

Unlike the classic rowing, the propulsion with blades or oscillating fins of transverse travel to the direction of advancement, the maximum propulsion is obtained at the beginning of the route in descending proportion to the right angle, or parallel to the advance line, in that position The exact direction of the water is transverse to the advance, which is useless to propel us, but from that point it becomes negative, which slows us down.

The known state of the art has tried to solve this problem by providing the oscillating device with a fin arranged in an independent axis concentric with that of the swing arm or rowing mechanism, and stops limiting the path of the fin, which allows it to swing in the opposite direction to the direction of the profile until it reaches the position of the stop and from that point to acquire the same direction, at an angle opposite to the profile, which is the propulsion position; but the transit of “accompaniment” without propulsion capacity until reaching the stops, is uselessly losing a large percentage of the total route.

If, for example, in an oscillating paddle of 100 centimeters in length, the fin represents 50% of the total, and both swing at 90º angles, the “accompanying” path that the fin takes to reach the propulsion position between the two limit stops, represents practically 50% of the total, without propulsion capacity; but, in addition, it forces to maintain constant the angle of the drive, because the angle of the fin remains with an invariable travel of 90º, which means that every degree that we reduce we are increasing the “percentage of accompaniment”, but, what usually occur, is that, when trying to increase the speed of the vehicle, the user increases the pace of drives, normally reducing the angle proportionally; Therefore, the more the frequency increases, in fact, the propulsion capacity is reduced. Many attempts have tried to increase the propulsion without solving the problem, reducing the angle between the stops and extending the proportional length of the blade, which increases the accompaniment travel in the same proportion, and also reduces the positive travel to the parallel with the line of advance entering before in negative angle; So there have been many attempts that intended to use fins with a rigid frame and a percentage of the flexible central surface, with very poor results. Therefore, in practice, there are no known water vehicles, currently propelled with oscillating mechanisms of this type.

In an ordinary propulsion with vertically positioned oscillating flap or blade, transverse movement to the direction of advancement, the tilting axis of the mechanism is located in the stern, behind the keel of the vehicle, which produces great oscillation of the course, inverse to the travel of the blade in both directions of the drive, greatly worsening the effective hydrodynamic coefficient. In other versions with horizontally positioned fins, the undulating effect occurs on the longitudinal flotation line, which has the same negative hydrodynamic effect.

It is known to use a tilting fin transverse to the advance line, located in a forward position to a central keel arranged at the stern, which coincides with the fin at an angle very close to the parallel of the advance line, however short that it is in both directions of the route, which supposes another great reduction of propulsion in the zone of positive propulsion, without solving the percentage of “accompaniment” and although the incidence on the course is smaller than if the fin oscillated behind the keel, produces constant oscillations in the transverse waterline, so in addition to a poor propulsion is not very stable. Currently there are no known practical applications of this system.

Improves the state of the art in the propulsion with oscillating fins, reflected in propulsions mainly for diving, where the fins are fixed to the sole of the diver's foot, in the same plane, (at an angle of 90º with respect to the leg) by means of footwear or the like, which extends from the tip of the foot in two parallel, rigid or semi-rigid rectilinear profiles; among which the central body of the fin is divided into a plurality of tilting segments, transverse to it, but in the same plane and of similar length, provided with independent axes that relate at each end to each of both profiles, of so that the position of each segment with respect to the distance to the hip or knee joint (depending on the user moving the fins with straight legs and the instep of the foot forced to the maximum, or bent, where the longitudinal of the fins at rest it is located in the parallel of the swimmer, but displaced, equivalent to the distance between the floor and the knee) and its corresponding axis, it is different and therefore the accompanying path and the entry point in negative angle also, which represents a huge hydrodynamic problem to know the optimal path that minimizes the percentage of accompaniment or the entry into negative propulsion, which is different Rent with respect to each of the fin segments, which make its use very complicated, much more taking into account that the swimmer or diver has to coordinate the path of two fins and the position of the instep at the same time, which is very complicated, so this type of fins have failed to replace conventional ones.

In accordance with the novel features of the present invention, the improved aquatic propulsion with oscillating fins provides for maximum utilization of the muscular energy used, which is finite; substantially improving the efficiency of the oscillating fins of the propeller, but also with an adequate positioning of the elements of the mechanism and the user, whose weight, in small floating structures, represents a large percentage of the total mass, which has a great impact on stability. And, for this, the handlebar that drives the tilting mechanism, its axis of rotation, the paddle and the oscillating fins, in that order, as well as a minimum percentage greater than 50% of the user's mass, will be located, centered with respect to the transverse line of the vehicle, and in front of the keels of the maneuvering axle. So that the oscillating movement of the fins during the advance takes place very close to the keels located in the stern, in parallel and to the greatest possible distance from the longitudinal center of the vehicle, since a centered keel represents a hydrodynamic obstacle of destabilization, much greater than if they are two, and they are located on both sides, because even with rowing opening angles greater than 50º, from 0º in both directions the maximum position of the blades is very close to the right or even angle, so the water is propelled in a direction very close to the parallel of the corresponding keel in both directions of the beginning of the route, with a high propulsion ratio, but, when approaching the end of the route, the direction of the water varies towards the keel to which approximates, tending to balance the vehicle, instead of destabilizing it. With angles below 30º in both directions, a large percentage of the displacement flow takes place between the two keels, with no special impact on the transverse or longitudinal waterline, but also because the length of the blades or fins is proportional and increasing, the farther they are from the axis of rotation of the oar, those with greater surface area and with a wider path are, therefore, those with the greatest amount of water displaced and the closest to the keels, so the oscillating effect on the course it is minimal, very different from what would happen if the fins moved behind the keels; in the same way, the eccentric position of the blades with respect to the lower face of the oar, according to claim 5 of the present specification, allows the maximum approximation of this in parallel to the structure of the vehicle minimally affecting the center of gravity during the advance; but, even, lowering it in the turning maneuvers, when the driving element of the central axis of the vehicle moves at a shallow depth with respect to the waterline, propelling it in opposition to the centrifugal force.

According to the mentioned characteristics, the handlebar and therefore the oar, can rotate 360 ° and the tilting drive can be carried out in any position; the course will be determined at all times by the intermediate point of the tilt path.

A propulsion such as the one proposed by the present invention is not known, where the corresponding oscillating fins are provided with independent and eccentric tilting shafts with respect to the lower plane of a single profile or tilted flattened rectilinear rowing.

Nor are known propulsions with oscillating fins, arranged vertically in the same plane, of similar height, but where the length of each fin is different, increasing proportionally to the previous one as they move away from the axis of rotation of the oar with respect to its own axis, in congruence with the greater or lesser route of the oar with respect to each point of its length, which guarantees the synchrony of all the blades during the “accompaniment” route between their respective limiting stops.

Nor is there any known mechanism for limiting the oscillating path of the fins such as that described in the present invention, which makes it possible to place all the blades or fins at the same angle and, at the same time, vary it at will at any time, regardless of the tilting path of the rowing, from an operating mechanism located at an accessible point of the handlebar, that makes it easy to know, even for a child, the maximum angle that the fins reach in each direction, and in what position to place the operating handle that relates to them, to obtain maximum propulsion capacity. And, in addition, that said mechanism is totally foreign to any structure that is not a direct part of the propeller, so that the handlebar can be turned in any direction, without limit, and without altering the position set in advance for the fins.

DESCRIPCION DE LA INVENCIONDESCRIPTION OF THE INVENTION

The invention consists of a steering and tilting drive handlebar, composed of a cylindrical profile (14), transverse to the direction of advance in the rest position, provided at its ends with two handles or handles (16) and a central vertical extension ( 13), with a hollow square profile, intended to connect consistently and without clearances to the square segment (12b) of the upper end of the cylindrical axis of rotation (12a), of the tilting mechanism, whose interior consists of a cylindrical hole (48) that passes through full length At the lower end, the axis (12a) is fixed at a 90º angle to the rounded end of the oar (11), which extends into a flat rectilinear profile, transverse to the handlebar (14) and, at the opposite end, the axes of oscillation (9) of the blades (1, 2, 3, 4, 5) cross the profile of the oar (11) from the upper plane and are fixed to the plane, counting for a large rectangular flattened head (27), and two threaded holes (28), equidistant from both sides of the shaft (9), with which they connect the conical head screws (49) that cross the profile (11), from the bottom plane, through the profile holes (47) conical, intended to leave the shafts (9) centered on the oar (11) centered and fixed even though the diameter of the hole (46) of the screw-like profile is greater than this; from that point they extend rectilinear and eccentric, with respect to the lower plane, to the opposite end; where, preceded by a conical tip (10), there are peripheral grooves (45), said shafts (9), are introduced into their respective holes (51), provided in one of the vertical edges of each fin (1, 2, 3, 4, 5), and when the conical end (10) of the shaft (9) coincides with the hole of the slotted elastic segment (8), whose diameter is smaller than the axis (9), it expands allowing the passage and then it is housed in said groove (45), so that it is perfectly fixed but allowing it to be easily released, by introducing a flat element into the groove of the segment (8) and, by turning it slightly, forces it to expand and allow its disconnection,

In parallel, and in contact with the lower plane of the oar (11), a rectilinear plate of flat profile (6) of similar width is placed, which has as many grooves (32) as axes (9) are fixed to the oar (11 ), intended to allow the path of the plate (6) but also limit it to the length of the plates, as they are transferred by them. In the same lower plane of said plate (6), the stops (7) are fixed, distributed in pairs and equidistant to both sides of each of the grooves (32), and, therefore, of each of the axes (9), parallel and eccentric, with respect to a single oar (11) with a flat profile, distributed longitudinally, at a progressive increasing distance equivalent to the length of each of the fins (1, 2, 3, 4, 5), in progression, from the shortest (1) and closest to the axis of rotation of the oar, to the longest (5), arranged at the far end,

In accordance with the invention, the set of blades (1, 2, 3, 4, 5), which reflect the drawings exclusively as an example in number of 5, but observing the principle of proportional length, can be as many as they agree ; It has limited the tilting path between two stops (7) on each side, fixed to the common flat profile plate (6), which can be moved forward or backward, and therefore also the stops (7) allowing to modify at will the maximum limit of the oscillating travel of the blades (1, 2, 3, 4, 5), independently of the rocking travel of the paddle (11). Said plate (6), has a fixing element (43), at its end closest to the axis of rotation (12a) of the oar (11), which connects with the hole (44) provided at the end of a plunger ( 33), which runs through a guide element (26) to an articulated shaft (41), common with the end of a connecting rod (34), which extends and connects with an axis (40) housed at the end of a plate eccentric (35) fixed to the central rotary axis (21) of the articulated mechanism; said axis (21) runs from that point, through the hollow interior (48) of the axis of rotation of the oar (12a), to its opposite end; where it consists of a peripheral groove (36), intended to accommodate the corresponding elastic ring (37) that fixes its position on the shaft (12a), but which allows it to rotate independently to it, extending from that point, once the profile is connected vertical square (13) fixed to the handlebar (14) with the square segment (12b), until conveniently exceeding, above the hole (42), centered with respect to the vertical of the hole (48) on a semicircular shaped plate (15) fixed in the center of the handlebar (14). In the plane of said plate (15) a plurality of radial grooves (17) are arranged, equidistant from the hole (42) and the shaft (21), the end of which is threaded (39) and has two opposing planes (38) in in line with the structure of the hole (29) of the support (18), provided in conjunction with the nut (22), as fasteners to the shaft (21); at the opposite end, it has a vertical groove that houses the operating handle (19) that tilts with respect to a transverse axis (25) that passes the rotating support (18) and said handle (19), whose lower edge arranged as a ratchet exceeds the lower plane only when the handle of the handle is parallel to the upper plane of the support and is confronted with respect to the radial grooves (17), bound at its edge inclined by an elastic element (20) fixed to the support (18) to be introduced in the slot (17) that the user decides to fix the position when the handle (19) is released, thereby determining the position of the plate (6) and the stops (7) with respect to the axes (9) that they limit the angle and the tilting path of the blades (1, 2, 3, 4, 5), so it can be adjusted, based on the maximum angle reached by the handlebar (14), to obtain the acceleration desired maximum, avoiding negative angle entry.

Propulsion occurs when the user applies his muscular force, in traction or thrust, on either of the two handles (16) provided on each end of the handlebar (14), or in opposite directions on both at a time; movement that is transmitted to the rotary axis (12a) and this to the profile (11) in which the fins (1,2,3,4,5) are arranged forcing them to move transversely and alternately in both directions producing the displacement of water and in correspondence the propulsion of the swimmer, object or floating vehicle, in the proposed direction, which corresponds to the intermediate point of the rowing route of the oar (11).

It should be noted that none of the elements that make up the structure of the propeller, has no previous limitation that prevents it from rotating 360 degrees; whereby the alternative tilting movement can be exercised at any time. The position in which we place the handlebar (14) before being operated, allows the structure to move forward, backward or turn, in any direction.

DESCRIPCION DE UNA REALIZACION PREFERENTE DE LA INVENCIONDESCRIPTION OF A PREFERRED EMBODIMENT OF THE INVENTION

In a preferred embodiment of the invention, the drive handlebar, rotation axis, paddle and fins, in that order, as well as a percentage of the user's mass greater than 50%, will be arranged in the center of the feed line, ahead of the maneuvering axis that represent the two keels (53), located in the stern and as far as possible from each other on both sides of the vehicle or floating object where the propeller is installed, but placing the axis of rotation of the oar to the smallest possible distance, so that the fin arranged at the opposite end runs close to the keels, so that the drive of the propellant element produces the minimum oscillations in the course and also reduces the turning diameter of the vehicle, giving it an extraordinary maneuverability .

A preferred embodiment of the invention would include the use of several oscillating fins, provided with independent and eccentric parallel axes, relative to the lower plane of a single flattened tilting profile, whose widths vary proportionally to the distance between its corresponding axis and the axis of rotation of the rowing, where each of the blades has limited its oscillating path in both directions by stops fixed to a common plate, whose position can be varied at will with respect to all the propeller blades at the same time, increasing or reducing the maximum angle, regardless of Describe the oar, which allows you to choose at all times the most appropriate angle to the speed of travel.

In the same way, the use of axes fixed to a single rectilinear profile and the system of fast fixation of the oscillating fins allows rapid exchange for others that, maintaining the length corresponding to their position, are of greater or lesser height, and even vary the number of fins to obtain the maximum possible propulsion power; in any field, and with any object or floating vehicle to which the propulsion proposed by the present invention is applied.

DESCRIPCION DE LOS DIBUJOSDESCRIPTION OF THE DRAWINGS

The drawings included herein are only an example for the understanding of the invention, not being limiting.

Figure 1 represents a drawing of the drive mechanism and the coupled propeller.

Figure 2 represents a drawing where the semicircular base and radial grooves are located, which are related to the ratchet mechanism.

Figure 3 represents a drawing of the components of the ratchet mechanism, support, handle / ratchet and elastic element that binds on the handle.

Figure 4 represents a drawing of the articulated mechanism, mounted on the rotating shaft and fixing means, and the means that is related to the plate that allows varying the angle of the blades and a cutting plane of the limit stops.

Figure 5 represents a drawing of the articulated mechanism of the drive.

Figure 6 shows a drawing from the lower plane, showing the situation of the paddle and the blades, advanced with respect to the position of the keels.

Figure 7 represents a drawing of the structure of the blades and the elastic segment to be fixed to the shaft.

Figure 8 shows a drawing of a blade showing the fixing profile of the shaft transformed into two segments.

Figure 9 represents a drawing of the profile of the rotary axis, the profile of the oar and the structure of the axes, as well as the elements that allow them to be fixed to the oar and fixed on these the blades.

Claims

Improved aquatic propulsion with high performance oscillating fins, which includes means to reduce the negative angle travel of an oscillating fin transverse to the advance line, characterized in that the oscillating fins (1, 2, 3, 4, 5), which represent Figures 1 and 7, of the present specification, in number of 5, but which may be formed by a different number, form a supportive propellant body, composed of segments arranged in the same longitudinal plane, of similar height, but of different length, and provided with independent oscillation axes (9), parallel to each other; where its greater or lesser length depends on the distance between its axis (9) of oscillation, and the axis (12a) of rotation of the oar (11), in equivalence to the diametral route of the oar (11) with respect to each point where fix its corresponding axis (9); being the length of the one that is farthest away, the one that marks the descending percentage; if it is for example 10%, all the fins will have a length equivalent to 10% of the distance between its own axis and the axis of rotation of the oar and so on.
Improved aquatic propulsion with oscillating fins of high performance, in accordance with claim 1, characterized in that the oscillating alternative path of the fins (1, 2, 3, 4, 5) is limited in both directions by two stops (7), equidistant on each side of its oscillation axis, fixed to a mobile, rectilinear, flat profile plate (6), arranged in parallel and in contact with the lower plane of the oar (11), of similar width, between it and the blades ( 1, 2, 3, 4, 5); in whose longitudinal center a series of grooves (32) are distributed, in number equal to that of axes (9) fixed to the oar (11); provided to allow the path of the plate (6), but also limit it to the length of the same, to be transferred by them; in the same lower plane of said plate (6), the stops (7), which limit the travel of the blades, are fixed; distributed in pairs and equidistant to both sides of each of the grooves (32), and therefore of each of the axes (9), so that the displacement of the plate (6), in either of the two directions , modify its maximum oscillating path.
Aquatic propulsion perfected with high performance oscillating fins, in congruence with claim 2, characterized in that said plate (6) has a fixing element (43), at its end closest to the axis of rotation (12a) of the oar (11 ), which connects with the hole (44) provided at the end of a plunger (33) that passes through a guide element (26) to an articulated shaft (41) common with the end of a connecting rod (34) that extends and connects with a second shaft (40) disposed at the end of an eccentric plate (35), fixed to the central rotary axis (21) of the articulated mechanism; said axis (21), runs from that point through the hollow interior (48) of the axis of rotation of the oar (12a), to its opposite end, where it consists of a peripheral groove (36), intended to accommodate the corresponding elastic ring ( 37) which fixes its position on the rotary axis (12a), but which allows it to rotate independently of it; extending from that point, once connected the square vertical profile (13) of the handlebar (14) with the square segment (12b), of the axis (12a), until it exceeds the hole (42), centered with respect to the vertical of the hole (48), in a semicircular shaped plate (15), fixed in the center of the handlebar (14); in the plane of said plate (15) a plurality of radial grooves (17) are arranged, equidistant from the hole (42) and the shaft (21), whose threaded end (39) has two opposing planes (38) in line with the structure of the hole (29) of the support (18), provided in conjunction with the nut (22) as fasteners of the shaft (21); at the opposite end it has a vertical groove that houses the operating handle (19) that tilts with respect to a transverse axis (25) that passes the rotating support (18) and said handle (19), whose lower edge, arranged as a ratchet, exceeds the lower plane only when the handle of the handle is parallel to the upper plane of the support and is confronted with respect to the radial grooves (17), bound at its edge inclined by an elastic element (20) fixed to the support (18 ) to be introduced in the slot (17) that the user decides to fix the position when the handle (19) is released, thereby determining the position of the plate (6) and the stops (7) with respect to the axes (9) that limit the angle and the tilting path of the blades (1, 2, 3, 4, 5), so it can be adjusted based on the maximum angle reached by the handlebar (14) in its alternative travel to obtain maximum propulsion and avoid entering at a negative angle.
Aquatic propulsion perfected with high performance oscillating fins, characterized in that the handlebar (14), axis of rotation (12), paddle (11) and fins (1, 2, 3, 4, 5), in that order, will be placed by in front of the two keels (53) located at the stern and as far away as possible from each other, on both sides of the vehicle or floating object where the propeller is installed, but placing the axis of rotation of the oar at the shortest possible distance, so that the fin arranged at the opposite end runs close to the keels, so that the drive of the propellant element produces the minimum oscillations in the course and also reduces the turning diameter of the vehicle.
Improved aquatic propulsion with oscillating fins of high performance, in congruence with claims 1 and 2, characterized in that the vertical axes (9), on which the fins (1, 2, 3, 4, 5) oscillate are fixed only on their upper end to a single flattened profile, constituted by the rocking oar of the propeller (11), extending rectilinear but eccentric with respect to it, so that it facilitates the maximum approximation of the oar in parallel to the sliding surface of the vehicle or floating object.
Improved aquatic propulsion with oscillating fins of high performance, characterized in that the axes (9), on which the blades or propeller fins (1, 2, 3, 4, 5) that cross the flat profile of the oar (11) from the upper plane, they have a wide rectangular flat head (27) and two threaded fixing holes (28), equidistant from both sides of the shaft (9), with which they connect the conical head screws (49) that cross the profile ( 11) from the lower plane, through the conical profile holes (47), intended to leave the axes (9) fixed and centered to the oar (11) although the diameter of the hole (46) that crosses the axis (9) is very superior to this one; characteristic that allows the exchange of damaged shafts (9), even when they receive sudden impacts in shallow areas that could otherwise render the propeller useless.
Aquatic propulsion perfected with high performance oscillating fins, in accordance with claims 1, 2 and 6 characterized in that said axes (9), at their lower end, have a peripheral groove (45) preceded by a conical tip (10) provided for that when introducing the shaft (9) through the hole (51) of the fin (1, 2, 3, 4, 5), when coinciding with the hole of the slotted elastic segment (8), of the fin (1, 2, 3, 4, 5), whose diameter is smaller than that of the shaft (9), expands, allowing the passage and subsequently being housed in said groove (45), so that it is perfectly fixed, but allows it to be easily changed, introducing a flat element in the groove of the segment (8) and, when turned slightly, expands, allowing disconnection; in the same way you can do without the expandable segment (8) and use instead the corresponding elastic ring of those that exist on the market, or use shafts (9) with the threaded end, which fix the fin in the proper position by middle of a lock nut; any of the referred systems allows the rapid disconnection, for the exchange of axes or fins.
Aquatic propulsion perfected with high performance oscillating fins, in accordance with claim 6, characterized in that the set of oscillating blades (1, 2, 3, 4, 5) are configured with different lengths depending on the distance between their axis (9) and the axis of rotation of the oar (12a), although its height may be similar; the body of the fin (1, 2, 3, 4, 5), is composed of a plate of rigid or semi-rigid material, presenting in one of the vertical edges a round profile (50) that extends partially with respect to the total height , whose center is perforated (51) to accommodate the shaft (9), of slightly smaller diameter, on which it oscillates; the round profile (50) can be partially sectioned and constitute two segments (23, 24), of a determined height at the ends, equally perforated, that reduce the total thickness of the fin body (1, 2, 3, 4, 5), improving its hydrodynamic coefficient; from the lower end of the round profile (50), the fin body has an elastic segment of the same profile (8), whose center is perforated in a smaller diameter than the oscillation axis (9) and has a diametral vertical groove (52) in the same plane as the fin body (1, 2, 3, 4 or 5), which allows it to expand, by introducing the conical tip of the oscillating shaft and finally being housed in the peripheral groove (45) provided to that end, on the shaft (9), so that it is perfectly fixed, the disconnection of both can be done easily, by introducing a flat element into the slot of the expandable segment (8) which, by turning it slightly, facilitates the disconnection.