Variable geometry propulsion system

Abstract

The invention is a traction device for a vehicle, such as a wheel or a track, comprising one or more movable parts, referred to as drive parts, which can change position from a position enabling propulsion on the ground to a position ensuring propulsion in a fluid or on its surface. The main applications are land vehicles capable of traveling on roads as well as on uneven or muddy ground and of traveling on or in water, such as a motor vehicle, a boat capable of navigating shallow waters, a submarine, or an aircraft capable of landing on a beach or on the water.

Description

Title of the invention: Variable geometry propulsion device technical field

[0001] The invention is a vehicle traction device that can adapt to the environment on which or in which it moves. Previous technique

[0002] We know of patent CN107962922A of April 27, 2018, by CUI JIE, LI QIAN, QIAO YANXIN, WANG YI, CHANG QI, ZHUANG CHENYI, SUN HONGLAI, CHEN ZHIPENG and CHEN YANG, which describes a track equipped with a plurality of paddles arranged on the outer end faces of the tracks and which provide propulsion for an amphibious vehicle in water. These paddles are permanently perpendicular to the outer faces of the tracks, so that they are not well suited for the movement of the vehicle on hard ground.

[0003] We know of CN108422821 (A) of August 21, 2018 by SUN SHILIANG which describes a similar device, which has the same drawback.

[0004] We know of CN110733305 (A) of January 31, 2020 by WANG XINGBO, LI XINYU and ZHANG SIMING which describes a moving part comprising a plurality of flexible blades ensuring the propulsion of a vehicle in water, but which is also poorly adapted to the circulation of a vehicle on a hard ground.

[0005] We know of US 10259280 (B 1) of April 16, 2019 by ROE RICHARD DARIN [US] which describes a vehicle equipped with wheels allowing it to roll on a ground, which have on their lateral part movable parts to ensure the propulsion of the vehicle on water, but the efficiency of the drive on water of this device is low.

[0006] We know of CN114619813A of June 14, 2022 by GAO SHENGYUN [CN] which describes a four-wheeled amphibious vehicle having water agitation plates which can be periodically extended and moved into a rest position, the switching between a land driving mode and an aquatic driving mode being able to be achieved by turning the angle of a cam but not automatically.

[0007] We know of WO2007079045A2 of July 12, 2007 by MUNSHAUR TODD [US] and VAN OSDELL STEVEN [US] which describes an amphibious vehicle equipped with floating amphibious traction wheels, the wheels having a number of foldable pockets arranged around the surface of the wheel and oriented in the direction of rotation of the wheel.

[0008] US Patent 1730758 (A) of October 8, 1929, by Edward Caldwell Jonathan, is known, describing an aircraft equipped with two rotating thrust devices to generate a thrust vector, each comprising wings with periodic adjustment creates a thrust vector normal to the rotor's axis of rotation. Such traction devices are often called cyclorotors.

[0009] We know of BRI 12023023953 (A2) of January 30, 2024 from HOFREITHER KLE-MENS [AT] and KINAST LUKAS [AT] which also describes such an aircraft.

[0010] We know EP3715249 (A2) of September 30, 2020 from CYCLOTECH GMBH [AT] which describes a means of controlling the wings of such an aircraft.

[0011] We know of RU2060203 (Cl) of May 20, 1996 by FEDCHISHIN VITALIJ G [RU] which describes a device comprising such cyclorotors providing propulsion for a ship which includes a means of accessing a flat shore by means of traction disc drums which can roll along an underwater plane. Technical problem

[0012] The devices described above do not allow a vehicle to automatically switch from a mode allowing quality driving as permitted with wheels or tracks on a smooth and non-slip surface such as a road or dry path, to driving on mud, snow or ice, or even to aquatic propulsion or aerial propulsion according to the principle of paddle wheels or cyclorotors.

[0013] A wheel according to the invention comprises at least one element, called a moving part, which can protrude from the track to provide propulsion in or on some of these different media, or even to ascend and descend stairs. The problem is complex because this moving part must not only deploy automatically when possible, but also retract automatically when it encounters an obstacle such as the ground, and if possible remain deployed both when moving forward and backward (if only to be able to brake in the event of aquatic or aerial use).

[0014] The position of the moving part when retracted is called the rest position above and below, and its position when deployed is called the working position, it being specified that in certain embodiments of the invention there may exist a position hereinafter called the retraction position in which the moving part is even more retracted than in its rest position, and a position hereinafter called the extreme projection position in which it is even more deployed than in its working position. Brief description of the drawings

[0015] The invention will be well understood, and other objects, advantages and features thereof will become more apparent from the reading of the description which follows, which is illustrated by figures 1 to 7.

[0016] [Fig. 1] is a perspective view of two wheels IA whose moving parts 21, 22 and following are sliding. These moving parts are blades on the left and Winter tire studs on the right. Elastic springs 31, 32, and following springs push them from their resting position to their working position. The wheel rolls on hard ground, and the lower moving parts are therefore retracted into the resting position, while the upper moving parts are in the working position. If this wheel were rolling on mud or fresh snow, the lower moving parts would be in the working position. This device is particularly suitable for airless tires.

[0017] [Fig.2] is two views from different perspectives of the same device functioning like a wheel, whose moving parts are wings that pivot to move from their rest position (left) to their working position (right). A wing 21 pivots relative to the wheel along the axis 51, and its inclination is determined by the position of the arm of an element 4 called a synchronizer which rotates around the axis 40 to determine sets of possible positions of the moving parts 21, 22, 23 and following.

[0018] This axis 10 of rotation of the wheel is here coincided with the axis 40 of rotation of the synchronizer, and all the wings are in the rest position.

[0019] [Fig.3] is a perspective view of two identical wheels that differ by the The distance from the hub is 40 mm from the assembly formed by the left part of the wheel and the wings. On the left, it is away from this assembly and the wings are in the rest position, while on the right it is closer to it, which increases the circumference of the synchronizer and moves the wings into the working position.

[0020] [Fig.4] is a perspective view of a wheel identical to those in the two figures previous ones, but which here works according to the principle of a cyclorotor. The axis 40 of rotation of the synchronizer is offset to the left with respect to the axis of rotation of the wheel, which leaves the upper and lower wings in their rest position, while those located on the left and those located on the right provide lift going to the left for a trigonometric rotation of the wheel, and to the right for a clockwise rotation.

[0021] [Fig.5] is a profile view of one in three different configurations, the parts The moving parts 21, 22, 23 and following are oriented differently depending on the direction of rolling. Those of the left and right wheels are in a traction position in a fluid, in one direction of rolling or in the opposite direction, while those of the center wheel are in a rest position, which gives this wheel the best rolling capabilities on the road.

[0022] [Fig.6] is a perspective view of a vehicle equipped with wheels 1A1, 1A2 and 1A3 according to [Fig.3], driving forward on road, then on soft ground and finally in water.

[0023] [Fig. 7] is a perspective view of a caterpillar according to the invention. The parts Mobile units 21, 22 and following are in the lower working position, ensuring propulsion on on soft ground, on or in water, while the upper sections are in a rest position. The elastic return springs are not shown, but two belts 61 and 62 are visible, forcing the upper moving parts of the IB track into a rest position. Description of the invention

[0024] The invention is a traction device for a vehicle such as a wheel (IA) or a track (IB) comprising a surface called a track (2) and a plurality of elements called moving parts (21, 22 and following), each capable of moving along a trajectory called the trajectory of the moving part, at least from a position called the working position in which it is partially protruding from said track to a position called the rest position in which it is located less protruding or inside the periphery of said track, characterized in that - said device includes an elastic return means (31) pushing said moving parts in the direction from their rest position to their working position, and this elastic return is less than a predetermined threshold called the first safety threshold, - and that the trajectory of the movement of said moving part is such that at least a part of said moving parts does not retract under the effect of a rotational moment applied to them, in the two directions of rotation called forward and reverse, if this rotational moment is less in said direction of rotation called forward than a predetermined threshold called the second safety threshold, and in said direction of rotation called reverse than a third predetermined threshold called the third safety threshold, it being specified that the above and below are understood - by rolling track, the rolling track that the said traction device would present if all said moving parts were in a rest position, - and by extending and retracting movements of a moving part going respectively in the direction from the rest position to the working position and vice versa Detailed description of the invention

[0025] The principle of the present invention is to equip the rolling path of a wheel or a track with a plurality of movable parts which can move to adapt automatically to the medium on which or in which the vehicle moves, a movable part thus placing itself in a so-called resting position when the vehicle rests on a solid ground such as a road, and in a so-called working position when the vehicle moves either on a soft ground such as mud or snow or on a slippery ground such as ice or black ice, or in a fluid or on its surface.

[0026] According to the invention, ideally it is necessary to:

[0027] - choose an elastic return such that it pushes the moving part in its working position from a determined threshold, so that it does not resist a determined centripetal radial force that would be applied to it, for example the contact of a blade with an obstacle or with the ground;

[0028] - and design the geometry of the device in such a way that the trajectory of a part mobile is such that the effect of a rotational moment applied to the wheel by a force exerted on the moving part, if it is less than a predetermined threshold, is not sufficient to make it move from its working position to its rest position.

[0029] The moving parts not retracting under the effect of a rotational moment applied to the wheel by a force exerted on them, in the two directions of rotation called forward and reverse, if this rotational moment is less in the direction of rotation called forward than a predetermined threshold called the second safety threshold, and in the direction of rotation called reverse than a third predetermined threshold called the third safety threshold.

[0030] The movement of the movable part can be arranged so that, when moving forward, it moves backward relative to the wheel's axis of rotation as it transitions from the working position to the rest position, and moves in the opposite direction relative to the wheel's axis of rotation when moving backward. This facilitates its retraction if it encounters an obstacle. If the movable part is moved by sliding, it is sufficient that the direction of the sliding be inclined relative to the radius of the wheel passing through the same point on the track.

[0031] A moving part can be a paddle, such as that of a paddle wheel for water propulsion, a protrusion on a tire or track for driving on muddy ground, or a cleat or series of cleats to prevent slipping on ice or black ice. A moving part can have all sorts of shapes, such as a plane, a hemisphere, a chevron, or a rod or a set of rods, depending on the intended use.

[0032] The moving part can be located inside the tread, and its movement into the working position can deform the tread. The device is then compatible with tubeless tires. A protrusion such as a chevron, for example, may only appear when the corresponding part of the tire is pushed outward by a moving part. The decrease in air volume resulting from this movement of a moving part leads to a decrease in tire air pressure, which can be compensated for or, conversely, maintained so that the tire adapts even better to uneven ground.

[0033] The travel of a moving part can be greater than that which moves it from the rest position to the working position, both inwards and outwards. rolling path to reach a so-called extreme retraction position, than outwards to reach a so-called extreme protrusion position.

[0034] The extreme protrusion position can for example cause the cleats to come out of the moving part and / or the rolling path, in addition to the coming out of classic protrusions allowing rolling on muddy ground.

[0035] An elastic means can advantageously be provided so that, when a moving part has been placed in its fully retracted position, it remains in equilibrium there. A similar means can maintain it in its fully extended position. In either of these two cases, the synchronizer or another mechanical means can serve to place a moving part in one or the other of these equilibrium positions. An advantage of this solution is that it can maintain all moving parts in a stable position throughout the rotation of the wheel or the entire cycle of a track, without friction between the moving part and the track.

[0036] The moving parts advantageously have an internal structure made of rigid but flexible materials and are easily removable for quick replacement. In the example shown in Figures 5 and 6, they constitute the tire tread and therefore their main wear parts, which means that the bulk of the tire can last longer.

[0037] It is advantageous for the position of a moving part to automatically return to its so-called resting position in the upper part of the track, in order to limit the overall size of the device and, above all, to avoid offering resistance to the forward movement of the vehicle, which is equipped with a wheel or a track according to the invention, when it is moving on or in water. This distinguishes the device according to the invention from older paddle wheels, the upper part of which could strike waves, thus hindering the boat's progress, and it allows the use of a wheel that is completely submerged. It also allows the use of wheels according to the invention with existing vehicles, preventing the moving parts from striking the wheel arch in the bodywork.This can be achieved by many means available to those skilled in the art, such as a stop fixed to the vehicle chassis preventing the deployment of the moving parts in the upper part of the device. Such a stop is made up of belts 61 and 62 on the track of the [Fig.7].

[0038] The designer of the device according to the invention chooses the elastic return force to determine the threshold above which the centripetal radial force causes the moving part to return to its rest position, and this threshold can advantageously be modified by the user or by a computer receiving information concerning the nature of the medium on or in which the vehicle is to move. In a simple version, such a means of modification is not essential.

[0039] It may be advantageous to limit by friction, for example by playing on the structure of the surfaces in contact during a sliding or rotation of a moving part, the possibility of retraction of a moving part when it is subjected to a significant torque resulting from resistance to the forward movement of the vehicle.

[0040] The device is advantageously equipped with a means called a synchronizer 4 for the moving parts, linking a plurality of moving parts together to determine sets of possible positions of the moving parts. Such a means is shown in Figures 2, 3, and 4. This synchronizer can advantageously undergo elastic deformation and have flexible parts. It can even be used as an elastic return 31.

[0041] In the case where the device according to the invention is a wheel, the synchronizer may consist of a mechanical assembly comprising a hub 40 connected directly or indirectly to all or some of the moving parts by rigid or flexible links. This mechanical assembly may rotate about the axis of the synchronizer, completing one full revolution for each revolution of the wheel.

[0042] The synchronizer's axis of rotation can be moved up and down, so that in its lowered position, the synchronizer moves the moving parts at the bottom of the wheel to their working position and has the opposite effect on those at the top. An elastic return pushing it downwards keeps the moving parts at the bottom of the wheel in their working position, but automatically returns them to their resting position when one of them encounters an obstacle such as the ground.

[0043] The rotation axis of the synchronizer can also be moved forward and / or backward. This movement allows the kinematics of the moving parts to be modified in order to move the location of the moving parts towards their rest and working positions.

[0044] A wheel can be made up of movable parts that are cyclorotor wings forming, in one of their positions, a circular track allowing it to roll on the ground. The synchronizer can be designed so that the wings propel the vehicle only when they move from front to back in their lower section; a preferred solution is for this propulsion to occur, as with conventional cyclorotors, when they move from top to bottom and bottom to top. The advantage of these two solutions is that the wheel can be completely submerged in water. These solutions are shown in Figures 2 to 4.

[0045] The moving parts are then wings, and they can be moved into the working position in the lower part of the track and into the resting position in the rest of the track, but it is advantageous to use the method applied to cyclorotors as shown in [Fig. 4]. This makes it possible to change the orientation of the thrust provided by the wings without changing the direction of rotation of the device, simply by shifting the axis of Synchronizer rotation. A vehicle equipped with such cyclorotor wheels can thus travel on the ground, propel itself on or through a fluid, or even fly. It also offers the advantage of virtually automatic wing cleaning when driving through mud or snow.

[0046] Advantageously, a position can be provided in which the hub 40 of the moving part is located on the axis of rotation of the hub 10 of the wheel. The moving parts are stationary relative to the rest of the wheel throughout the wheel's rotation. There is then no friction due to the movement of the moving parts from one position to another. [Fig. 3] shows how all the moving parts can thus be maintained in their rest position or in their working position. The position of all the moving parts is determined by adjusting the distance between the wheel hub and the synchronizer hub.

[0047] This may be suitable, for example, when the moving parts are studs or sets of studs protruding from the tread when the ground is icy. This particular configuration can be achieved by causing a suitable deformation of the synchronizer, the hub here also being located on the axis of rotation of the wheel

[0048] When the wheel is driven by means of a shaft connecting the motor to the wheel, it is difficult to position the synchronizer hub on the wheel's axis of rotation if the hub does not have a central recess allowing the shaft connecting the motor to the wheel to pass through. In this embodiment, the synchronizer hub is bulkier and can also be more expensive to manufacture, particularly if it incorporates ball bearings. One solution is to position it on the side of the wheel opposite the vehicle chassis, as shown in Figures 2 to 4.

[0049] In a particularly advantageous embodiment, not shown, the motor of a wheel according to the invention is located in the wheel itself. In this case, the wheel no longer has an external drive hub shaft, and the synchronizer hub can be located on the wheel's axis of rotation to determine the position of all moving parts, while being situated on the side connecting the wheel to the vehicle chassis.

[0050] It is also possible to use a hubless wheel driven by its rim, to obtain the same advantage.

[0051] When the device according to the invention is a track, the synchronizer can elastically push the lower moving parts towards their working position. Advantageously, it simultaneously and continuously pushes the upper parts towards their rest position. This can be a simple stop, a rail, a cable, or belts 61 and 62 as shown in [Fig. 7].

[0052] It is advantageous that the moving parts do not cause water or mud to rise upwards when they pass from the lower part of the device to its upper part, as this represents not only unnecessary bulk, but above all a loss. energy consumption reduces the device's efficiency in certain use cases. Consequently, it is advantageous for the device according to the invention to be equipped with a means acting directly or indirectly on the moving parts located in the upper part of the raceway so that they are automatically placed in a rest position or in a so-called extreme retraction position, which is even more retracted than the rest position. In an improved version, the moving parts can even be maintained in a rest or extreme retraction position in at least 75% of their highest positions.

[0053] The synchronizer can advantageously be constructed of a material or have an architecture that allows it to undergo elastic deformation. This means that, if the friction due to the movement of a moving part from one position to another exceeds a certain threshold, it can deform to cease producing the expected effect, and thus avoid causing damage to the moving part in question or to the synchronizer itself.

[0054] Without departing from the scope of the invention, a wheel may be fitted with one or more circular flanges allowing it to roll on the ground. The same applies to a track that may be fitted with an auxiliary track supporting part or most of the weight of the vehicle.

[0055] In a particular embodiment, the wheels or tracks constituting the device according to the invention can be floating, and even provide the vehicle's buoyancy on their own when it drives on water.

[0056] Wheels or wheel parts located between the moving parts, inflated at low pressure or made of very flexible materials, can ensure comfortable rolling and efficient propulsion on uneven ground. This also applies to tracks or track links.

[0057] The present invention is particularly suited to airless wheels that have an internal structure made of rigid but flexible materials, allowing them to deform and providing comfort practically equivalent to that of conventional inflated tires. Indeed, the use of these airless wheels makes it easiest to design wheels with housings to allow the retraction of moving parts.

[0058] In a particularly advantageous embodiment for high-speed road traffic, the moving parts comprise a portion of said tread, these portions forming almost the entire tread of the device when all the moving parts are in their rest position. This embodiment is shown in Figures 5 and 6 and is compatible with conventional inflated tires. These moving parts are preferably flexible and include the tire tread, which can therefore be omitted. Various types of moving parts more specifically adapted to different environments such as asphalt or soil, or mud, snow, ice or water.

[0059] The moving parts shown in Figures 5 and 6 are positioned differently depending on whether they propel the vehicle forwards or backwards. When the wheel changes direction of rotation, the rotational moment applied to it by the resistance force applied to moving parts on water or soft ground causes them to move from one position to another opposite to it, but does not cause them to retract.

[0060] In the case where the traction device is a track, a moving part may be a portion of this track that can pivot around an axis substantially parallel to the axis of rotation of one of said wheels supporting said track as shown in [Fig.7].

[0061] Advantageously, the traction device is equipped with a means of determining the position of the moving parts according to different rules to adapt to the environment on which or in which the vehicle moves.

[0062] A mechanical means not shown may be provided so that certain moving parts automatically move to a rest position when the force exerted by the traction device on the vehicle chassis exceeds a certain value, so that it automatically moves to a rest configuration.

[0063] The user or a computer can choose to keep the moving parts permanently in a so-called rest position when the vehicle is traveling on the ground, and to cyclically move them from this position to a so-called working position when it is traveling on mud or water. Positioning rules for the moving parts can be chosen according to the nature of the terrain, which can be analyzed by computer to determine the most appropriate rule.

[0064] The optimal position of each moving part can also be achieved by very simple mechanical means. A moving part can, for example, be held in its working position by an elastic return, the resistance of the terrain or fluid on which the vehicle is moving being able to modify this position to bring it closer to the so-called rest position. This makes it possible to travel on irregular surfaces such as uneven ground or shallows. It is thus possible to navigate on rivers or streams considered unnavigable, or to navigate safely in unfamiliar areas.

[0065] All means known to a person skilled in the art who is familiar with cyclorotor technologies, which allow the position of the moving parts to be varied according to their position in the cycle, can be implemented.

[0066] The invention is also a vehicle equipped with a traction device according to the invention described above.

[0067] It is also the method of propelling a vehicle by a traction device according to the invention described above. Applications

[0068] The main applications of the present invention are land vehicles capable of traveling on roads as well as on uneven or muddy ground and of sailing on water, or in certain versions taking off and landing vertically and flying in all directions, as well as boats, submarines navigating in the water or on the seabed, and aircraft, all of these vehicles being able to land on a beach or shoals. These vehicles can be used for leisure or work, but also for military combat. They can be piloted by humans, whether passengers or not, using radio controls, or by computers. Drones and toys also constitute important applications.

[0069] Reference numbers used in drawings - AI: wheel - IB: caterpillar - 10: wheel hub - 2: rolling track - 21, 22 and following: movable parts - 31, 32 and following: elastic returns of the moving parts - 4: synchronizer - 40: synchronizer hub - 41, 42 and following: axes of rotation of the moving parts with the synchronizer - 51, 52 and following: axes of rotation of the moving parts with the wheel - 61 and 62: belts forcing the upper moving parts of the IB track to move into the rest position.

Claims

Demands

1. A vehicle traction device such as a wheel (IA) or a track (IB) comprising a surface called a track (2) and a plurality of elements called moving parts (21, 22 and following), each capable of moving along a trajectory called the trajectory of the moving part, at least from a position called the working position in which it is partly protruding from said track to a position called the rest position in which it is located less protruding or within the periphery of said track, characterized in that - said device comprises an elastic return means (31) pushing said moving parts in the direction from their rest position to their working position, and this elastic return is less than a predetermined threshold called the first safety threshold,- and that the trajectory of the movement of said moving part is such that at least a part of said moving parts does not retract under the effect of a rotational moment applied to them, in the two directions of rotation called forward and reverse, if this rotational moment is less in said direction of rotation called forward than a predetermined threshold called the second safety threshold, and in said direction of rotation called reverse than a third predetermined threshold called the third safety threshold, it being specified that the terms above and below mean - by rolling track the rolling track that said traction device would present if all said moving parts were in a rest position, - and by extending and retracting the movements of a moving part going respectively in the direction going from the rest position to the working position and vice versa.

2. Traction device according to claim 1 characterized in that said moving parts do not retract under the effect of a rotational moment of said device applied to them, in the two directions of rotation said forward and reverse, if this rotational moment is less in the direction of rotation said forward than a threshold said second predetermined safety threshold, and in the direction of rotation said reverse than a third predetermined threshold said third safety threshold.

3. Traction device according to claim 1 characterized in that it is equipped with a means called synchronizer (4), linking a plurality of moving parts together to determine sets of possible positions of moving parts (21, 22, 23 and following).

4. Traction device according to claim 3 characterized in that said means called synchronizer (4) is used as elastic return (31).

5. Traction device according to any one of the preceding claims characterized in that it is provided with a means acting directly or indirectly on the moving parts located in the upper part of the rolling track so that they are automatically placed in a rest position or a so-called extreme retraction position because it is even more retracted than said rest position.

6. Traction device according to claim 1 characterized in that it is a wheel (IA) and that said wheel comprises a motor located in said wheel itself.

7. Traction device according to any one of the preceding claims characterized in that each moving part comprises a portion of said track said moving part comprises a portion of said track, these portions forming almost the entire tread of said device when said moving parts are all in rest position.

8. Vehicle equipped with a traction device according to any one of the preceding claims.

9. A method of propelling a vehicle by means of a traction device according to any one of claims 1 to 7.

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