Wheel generator with coupling system

Abstract

The present invention relates to a wheel generator, in particular a converter for generating electrical energy in a rolling wheel of a vehicle from deformation of the wheel tyre due to contact with the road, a system for generating electrical energy including said converter, as well as a vehicle or wheel including said system.

Description

[Technical field]

[0001] The present invention relates to a wheel generator, in particular a converter for harvesting electric energy in a rolling wheel of a vehicle from deformations of the wheel tyre due to contact with the road surface. In particular, the present invention relates to a converter having the features of the preamble of claim 1. The present invention also relates to a system for harvesting electric energy, as well as to a vehicle or wheel comprising said system. [Background technology]

[0002] Vehicle tires, especially pneumatic tires, are deformed during the rolling process when a load is applied in the area of ​​the contact surface. During this process, the tire is bent and there is a loss of energy during power transmission due to heating. This effect is called flexure.

[0003] The force required to flex a tire is the main component of the rolling resistance and acts against the driving force of the vehicle. On the one hand, increased flexion thus directly leads to an increase in the fuel consumption of the vehicle and can even reduce the service life of the tire. On the other hand, a certain deformation of the tire, and therefore an increase in the contact area of ​​the tire on the ground, is highly desirable for the purpose of increasing the traction coefficient of the vehicle and also for the purpose of increasing driving comfort. Therefore, the air pressure in a pneumatic tire is typically set at a compromise between flexion and the traction of the vehicle.

[0004] The energy losses due to tire flexion are, together with air resistance, one of the main components of the total energy losses in a vehicle. Therefore, the development of systems for recovery (in particular for powering the vehicle battery) based on utilizing the flexion of vehicle tires has been of interest for the last few years, especially in the field of electric vehicles.

[0005] Various methods and systems for harvesting energy on or within a vehicle tire are known in the prior art, primarily for supplying electrical energy to various tire monitoring sensors, e.g., tire pressure sensors, located within the tire.

[0006] US Patent No. 5,399,431 therefore discloses a generator within a tire, where a reciprocating motion is generated using the slight deformation and reduced space that occurs on the inner side of the tire between the wheel and the tire when in contact with the ground, and a device is activated to rotate a generator.

[0007] Furthermore, Patent Document 2 discloses an energy converter for generating electrical energy in a rolling wheel of a vehicle by utilizing the elastic deformation of the wheel between the driving surface and the central axis of the wheel, the energy converter having a lever element with a protruding arm rotatably mounted about a rotation axis, the lever element being configured to be arranged on the wheel of the vehicle such that deformation of the tread towards the central axis of the wheel generates a force acting on a contact surface of the protruding arm, the force acting on the contact surface causing a rotational movement of the protruding arm in the direction of pump rotation about the rotation axis.

[0008] However, in converters known in the prior art, direct contact with the wheel tire occurs between a lever or a protruding arm that is rigidly connected to the rim. It has been shown that at higher speeds, perhaps with typical automobile tires up to about 50 km / h, direct contact between the lever and the wheel tire results in significant heating of the tire material at the contact point, softening and increasing the stickiness of the tire material, damage to the wheel and therefore ultimately failure of the generator.

[0009] US Patent No. 5,399,633 discloses a vehicle with a mechanical and preferably hydraulic pump inside the tire. As the tire rotates, the weight of the vehicle pumps water in a storage tank. The pressure in the storage tank is used to drive the vehicle directly or indirectly. The pump is driven by a bracket that holds rollers. These contact specially designed beads inside the tire.

[0010] In all transducers known in the prior art, the lever elements are furthermore arranged at an angle much less than 45° to the inner surface of the tire. On the one hand, this reduces the forces that arise as a result of direct contact between the lever and the inner surface of the tire at the contact point. However, on the other hand, this reduces the effective displacement of the lever elements, i.e. the angular range that they pass through during their movement.

[0011] Finally, many converters proposed in the prior art are very demanding in terms of the space they require inside the tire, which makes it substantially more difficult to replace the tire while it is on the rim. In some cases, the wheel, and in particular the rim, must be dismantled and the converter removed before the tire is replaced. Therefore, the most compact possible design of the converter is desirable, in particular to allow tire replacement on the rim without removing the converter. At the same time, however, it is essential to ensure a consistent and reliable transmission of the considerable forces that act on the lever element and that need to be transmitted to the generator. [Prior art documents] [Patent documents]

[0012] [Patent Document 1] International Patent No. WO2015 / 054763 A1 [Patent Document 2] European Patent No. EP3540 921 A1 [Patent Document 3] US Patent No. 2004 / 0130157 A1 Summary of the Invention [Problem to be solved by the invention]

[0013] The object of the present invention is to provide a converter for harvesting electrical energy in a rolling wheel of a vehicle from deformations of the wheel tyre due to contact with the road surface, which does not have the problems of the prior art and in particular is highly efficient, ensures reliable operation even at higher speeds and is as compact as possible to allow tyre changes on the rim without dismantling the converter. [Means for solving the problem]

[0014] This object is achieved according to the invention by means of a converter for obtaining electric energy in a rolling wheel of a vehicle from deformations of the wheel tire due to contact with the road surface, comprising at least four lever elements rotatably housed at their first ends and configured at their second ends to come into contact with the inside of the wheel tire via at least one contact element, such that deformations of the wheel tire due to contact with the road surface cause a rotational movement of the lever elements, a mechanical coupling element system suitable for transmitting forces generated due to the rotational movement of the lever elements, and at least one generator configured to convert forces preferably transmitted by the mechanical coupling element system into electric energy, wherein the lever elements are each pivotally mounted at their first ends by a shaft configured to transmit a rotational movement force, the mechanical coupling element system per shaft of each lever element having at least two coupling elements each arranged to transmit the rotational movement force to the shaft of an adjacent lever element or to an intermediate shaft, and wherein there is at least one planetary gear system arranged to transmit the rotational movement of the shaft or intermediate shaft to the generator.

[0015] The invention is based on the realization that in the case of known generators, the levers or protruding arms of the generator, which are rigidly connected to the rim, cause friction when they come into direct contact with the inside of the wheel tire, resulting in strong local heating. The wheel tire performs a non-linear movement relative to the rim during its bending movement, i.e. starting from the rim as a reference system, the movement of a given part of the wheel tire that comes into contact with the road surface is not in a straight line during the wheel rotation, but circumscribes the surface. In the case of a lever or protruding arm that is merely rotatably mounted, a relative movement of the corresponding contact surface of the wheel tire and the contacting lever or protruding arm thus occurs when the wheel rotates, resulting in friction between them. The latter seems to lead to failure of the known generators, especially at higher speeds, as low as more than approximately 50 km / h for a typical car tire. Moreover, the lever element is arranged at an angle well below 45° to the inner surface of the tire. On the one hand, this reduces the forces and friction that occur as a result of the direct contact of the lever with the wheel tire at the contact point. However, on the other hand, this reduces the effective displacement of the lever elements, i.e. the angular range that they pass through during the movement.

[0016] Secondly, the systems known in the prior art are very demanding in terms of the space they require inside the tire, which makes it substantially more difficult to change the tire while it is on the rim. In some cases, the wheel, and in particular the rim, must be disassembled and the converter removed before the tire can be changed.

[0017] According to the invention, and surprisingly, these problems can be solved by a combination of measures, in particular because, on the one hand, at least one contact element, typically a roller or a roller member (roller segment), is rotatably housed at the second end of the lever element, such that the contact element establishes contact with the lever element and the wheel tire and the axis of rotation of the contact element extends substantially parallel to the axis of rotation of the wheel. The contact element is rotatably housed at the second end of the lever element around the axis of rotation and establishes contact with the lever element and the wheel tire. Thanks to its rotatable mounting, it is possible to compensate the relative movement of the wheel tire and the lever element through its own rolling movement, and thus to minimize or prevent friction between the wheel tire and the lever.

[0018] On the one hand, the particular arrangement of the mechanical coupling element system with at least two coupling elements for each shaft of each lever element, which coupling elements are arranged to transmit the power (energy) of the rotary motion to the shaft or intermediate shaft of the adjacent lever element, allows a very compact design that allows a reliable transmission even for large forces. In addition, in the presence of at least one planetary gear arranged to transmit the rotary motion of the shaft to the generator, the power transmission from the mechanical coupling element system to the generator can be made possible with minimal space requirements while realizing an appropriate gear ratio.

[0019] The invention will now be described in more detail based on preferred embodiments.

[0020] A converter according to the invention for obtaining electric energy in a rolling wheel of a vehicle from deformations of the wheel tire due to contact with the road surface comprises at least four lever elements rotatably housed at their first ends and configured at their second ends to come into contact with the inside of the wheel tire via at least one contact element such that deformations of the wheel tire due to contact with the road surface cause a rotational movement of the lever elements. The wheel typically comprises a rim and a wheel tire that can be filled with compressed air.

[0021] The rotational movement of the lever element is typically understood as a partial rotation (pivot movement) of the lever element around the rotation axis N at the first end. The lever element is therefore specially designed to detect the deformations of the wheel tire occurring in the area of ​​the contact surface by the contact element during the rolling process of the load wheel rolling on a substantially horizontal driving plane and to convert them into a rotational movement around the rotation axis N at the first end of the lever element. The lever element is therefore not in direct contact with the inside of the tire itself, but rather is only in contact with it via at least one contact element. According to one embodiment of the transducer, the contact element or lever element is therefore configured such that the contact surface of the contact element of the lever element is designed to establish contact with the inner surface of the tire of the wheel.

[0022] Each lever element is rotatably mounted at its first end, preferably on the support structure or rim of the wheel. In principle, the direction of rotation N at the first end of the lever element can have any direction that extends substantially parallel to its corresponding contact surface on the inside of the wheel tire, since a bending movement of the inside of the wheel tire, i.e. a movement towards the rim, can cause a partial rotation of the lever element. In one preferred embodiment, the fulcrum of the lever element extends substantially parallel to the rotation axis of the wheel.

[0023] Within the scope of the present invention, substantially parallel preferably means a deviation from parallelism of less than 10°, and preferably less than 5°.

[0024] In one preferred embodiment, the lever element is designed in one piece. In this embodiment, it preferably supports one, in particular only one, contact element, which is rotatably mounted thereon. In an alternative similarly preferred embodiment, the lever element is formed of at least two members, i.e. consists of at least two, preferably only two members, which are mechanically connected and preferably partially rotatable relative to each other. By way of example, the first member of the lever element forms the first end to which the lever element is rotatably mounted, and the second member constitutes the second end supporting the contact element. The first member being partially rotatable relative to the second member allows the rotational movement (rocking movement) of the lever element to be compensated during the contact of the contact element with the inside of the bent tire and, at the same time, the contact of the contact element with the inside of the tire to be maintained. In this alternative embodiment, the lever element, preferably each lever element, preferably supports at least two, in particular only two, contact elements, which are rotatably mounted on the lever element, in particular on the second member. Particularly preferably, in an alternative embodiment, the lever element therefore consists of a first member having a first end and a second member constituting a holding element for at least two, preferably two, contact elements, thus preferably constituting a rolling slide. The latter is configured so that both contact elements can be in contact with the inside of the wheel tire (the inner surface of the tire) at the same time. In this way, the contact surface at the inside of the wheel tire is increased and thus the point force and therefore the point load of the wheel tire is reduced. The second member (hereinafter also referred to as "slide") is mounted so as to be partially rotatable on the lever element in such a way that when the lever element is "pulled out", for example from a rest position, contact of all contact elements held by the slide with the wheel tire is made possible. In one preferred embodiment, the distance between the rotation axes of the contact elements held by the (respective) slides is approximately equal (±10%, preferably ±5%) to the distance between the rotation axes of two adjacent contact elements of the second (directly) adjacent lever element when the contact elements are in contact with the inside of the wheel tire.As an example, the distance between the rotation axes of the second contact elements carried by each of the slides of the preferably 8 or 12 lever elements is preferably approximately equal (±10%, preferably ±5%) to the distance between the rotation axis of the contact element of the first slide and the rotation axis of the nearest contact element of the (directly) adjacent slide. In other words, the angle β through which the two rotation axes of the contact elements of the slides extend relative to the rotation axis of the wheel is preferably approximately 360° / 2*n, n being the number of lever elements or slides. The angle β through which the two rotation axes of the contact elements of the slides extend relative to the rotation axis of the wheel is therefore approximately (±10%, preferably ±5%) half the angle α between the two lever elements. The angle α is the angle through which the rotation axes of the two adjacent lever elements (as shown in FIG. 6), in other words the rotation axes of the slides also extend relative to the rotation axis of the wheel when the lever elements are in the same position. The angle α therefore corresponds to 360° / n, n being the number of lever elements. In this embodiment, the force distribution is evenly distributed over the wheel tire (the inner surface of the tire) since the contact elements contact the wheel tire at approximately the same distance. With 12 lever elements and two rollers per slide, 24 approximately evenly (±10%, preferably ±5%) spaced contact elements are in contact with the inner side of the tire (the angle β between each adjacent contact element, both of the two contact elements of one slide and between each adjacent contact element of two adjacent slides is then approximately 15° (±10%, preferably ±5%)). Contact elements that are more or less evenly spaced over the inner side of the tire also result in a more uniform transfer of energy to the lever elements, since this means that in typical bending deformations, for example of car or truck tires, at least two lever elements are always displaced simultaneously through their slides.

[0025] In one embodiment, the preferably two contact elements of the slide, preferably when they are designed as rollers, are surrounded or wrapped by a belt or strap. The belt or strap extends, for example, directly around both rollers or additionally around a deflection roller, which is also arranged on the slide. The surrounded contact elements, preferably rollers, in this case contact the inside of the tire via the belt or strap. This increases the effective contact surface of the contact elements with the inside of the tire and thus reduces the point load and therefore the load on the tire. The belt is designed, for example, as a V-belt or multi-V-belt to prevent the rollers from coming off.

[0026] In one preferred embodiment, the converter has at least 6, in particular at least 6 to 16, most preferably 8 to 12 lever elements.

[0027] In one preferred embodiment, the converter has in particular at least 6 to 16, most preferably 8 to 12, lever elements arranged rotationally symmetrically around the axis of rotation of the wheel.

[0028] The lever element of the transducer according to the invention comprises at least one contact element, via which the lever element comes into contact with the inside of the tire, such that a deformation of the wheel tire due to contact with the road surface causes a (partial) rotational movement of the lever element. This means that the (each) lever element has at least one contact element which is rotatably mounted in or on the lever element at its second end, such that the contact element establishes contact between the lever element and the wheel tire.

[0029] The (each) lever element preferably does not come into direct contact with the inside of the wheel tire (under normal operation) in any position of rotation about its axis of rotation N at its first end, i.e. the lever element does not touch the inside of the wheel tire. Rather, only the contact element comes into contact with the inside of the wheel tire, i.e. the contact element touches the inside of the wheel tire when the lever element is accordingly rotated about the axis of rotation at its first end towards the tire surface (away from the rim). The axis of rotation of the contact element is substantially parallel to the axis of rotation of the wheel. If two or more contact elements are present on the lever element, their axes of rotation are parallel. The possibility that the contact elements are, on the one hand, rotatably mounted on the lever element and, on the other hand, can rotate about an axis lying substantially parallel to the axis of rotation of the wheel allows the relative movement of the wheel tire and the lever element to be compensated and thus the friction between the wheel tire and the lever element to be minimized. The contact element is preferably, with respect to its dimensions, substantially rotationally symmetrical with respect to its axis of rotation, at least in the area in contact with the inside of the wheel tire. In particular, the contact element is therefore a roller or a partial roller (roller segment). The roller has a substantially cylindrical shape (the rotation axis of the contact element then corresponds to the cylindrical axis) with a possibly circular outwardly curved cylindrical outer surface (barrel-shaped rollers). Typical preferred radii of the contact element, i.e. preferably the roller radius, are such that the ratio of the radius of the contact element to the inner radius R of the wheel tire (around the center of the wheel) is in the range of 0.04 to 0.08, preferably 0.05 to 0.07. Typical suitable roller radii, in particular for automobile tires, are in the range of 18 mm to 30 mm. The contact element is preferably freely rotated about its fulcrum, in particular freely rotated 360°. This means that the contact element can preferably rotate freely about an axis of rotation about which the contact element is rotatably mounted or fixed to / in a lever element or slide, in particular completely about its own axis. This ensures a uniform contact of the contact element with the inner side of the wheel tire even at higher speeds.

[0030] According to one preferred embodiment, the ratio (A / R) of the distance A of the fulcrum N of the lever element from the wheel centre M to the inner radius R of the wheel tyre is in the range of 0.55-0.60, preferably 0.56-0.59.

[0031] According to one preferred embodiment, the ratio (B / R) of the distance B of the fulcrum N of the lever element from the contact point K of the contact element with the inside of the wheel tire (in case of multiple contact elements per lever element, the one having the greatest distance from the fulcrum N) to the inner radius R of the wheel tire is in the range of 0.44 to 0.55, preferably 0.45 to 0.53, in particular 0.46 to 0.50.

[0032] In the converter according to the invention, the lever element rotatably housed at the first end can contact the inside of the wheel tire via at least one contact element, which means that the sum (A+B) of the distance A of the fulcrum N of the lever element from the wheel center M and the distance B of the fulcrum N from the contact point K of the contact element with the inside of the wheel tire (in case of multiple contact elements per lever element, the contact point having the greatest distance from the fulcrum N) is greater than the radius R of the inside of the wheel tire ((A+B) / R)>1).

[0033] The displacement of the lever elements, i.e. the angular range which they pass through during their movement, is preferably significantly increased if the sum (A+B) of the distance A of the fulcrum N of the lever element from the wheel center M and the distance B of the fulcrum N from the contact point K of the contact element with the inside of the wheel tire, but with the maximum distance from the fulcrum N in case of several contact elements per lever element, is in the range of 102% to 110%, in particular 103% to 107%, ((A+B) / R)) relative to the radius R of the inside of the wheel tire. This value range for (A+B) / R means a significantly more "extended" arrangement of the lever elements compared to the prior art, such that the lever elements are arranged almost perpendicularly opposite the inside of the tire. This increases the forces and the relative movement between the wheel tire and the lever elements, but it allows high efficiency in the current situation, only by increasing the angular range which the lever elements pass through during their movement, which can ensure effective driving of the generator.

[0034] Radius R always refers here to the radius of the unloaded tire from the center of the wheel to the inside of the wheel tire (the inner surface of the tire). Fulcrum N of the lever element refers to the fulcrum of the lever element at its first end.

[0035] The converter according to the invention further comprises a mechanical coupling element system, which is configured and suitable for transmitting the force (energy) generated due to the rotational movement of the lever elements, in particular to a generator, preferably. The mechanical coupling element system in this case comprises at least two coupling elements per axis of each lever element. Typical suitable coupling elements are gears and axles, belts, chains and the like. The coupling elements preferably comprise at least one chain, or belt, in particular a toothed belt and / or a multi-V belt. The mechanical coupling element system in this case also typically comprises corresponding means for engagement of the axis of the lever elements with the coupling elements, for example gears, grooved wheels and the like.

[0036] The forces (energy) of all lever elements of the converter are preferably transferred to a (common) mechanical coupling element system, for example a set of chains or belts, in particular a toothed belt and / or a multi-V belt. The mechanical coupling element system preferably comprises at least two coupling elements per axis of each lever element, all axes of the lever elements being in frictional connection with the respective adjacent axes of the lever elements or through the coupling elements, in each case by the mechanical coupling element system, via intermediate axes. The lever elements are preferably arranged rotationally symmetrically around the rotation axis of the wheel, i.e. in a ring, so that a "closed ring" is preferably established, which means that all axes of the lever elements are in frictional connection with the respective adjacent axes of the lever elements around the wheel via coupling elements by the mechanical coupling element system. The number of coupling elements of the mechanical coupling element system therefore preferably corresponds to the number of axes of the lever elements. In other words, preferably there are no intermediate axes.

[0037] The mechanical coupling element system thus enables a frictional connection between all lever elements of the converter. This allows the generator to be driven more seamlessly. The mechanical coupling element system is also preferably in frictional connection with a number of, most preferably all, generators of the converter. By distributing the total energy generated by the lever elements to several generators, they can be operated seamlessly, allowing efficient energy recovery with minimal material input.

[0038] In one preferred embodiment, the converter therefore comprises a mechanical coupling element system, designed as a belt, in particular a V-belt, toothed belt or multi-V-belt, and establishing a frictional connection of all generators, preferably 3 or 4 generators, with all lever elements, preferably 8 or in particular 12 lever elements, of the converter. In this case, the belt is preferably guided around a roller or gear connected to the axis of the lever element and around a roller or gear connected to the axis of the adjacent lever element, respectively. In one embodiment, there may be one or more intervening freewheel rollers, or rollers on an intermediate axis, connected via coupling elements. Preferably, there are no intervening freewheel rollers, or rollers that are not connected to the axis of the lever element and / or only to the generator. In the most preferred embodiment, the converter therefore comprises a mechanical coupling element system, including 12 belts, in particular a V-belt, toothed belt or multi-V-belt, and providing a frictional connection of all axes of the 12 lever elements.

[0039] Finally, the converter according to the invention comprises at least one generator configured to convert the force (energy) obtained by the rotational movement of the lever elements and preferably transmitted by the mechanical coupling element system into electrical energy. In one preferred embodiment, the converter has at least two, in particular at least 2 to 12, most preferably 3 to 8, for example 3 or 4 generators arranged rotationally symmetrically around the rotation axis of the wheel. The number of lever elements is preferably a multiple of the number of generators.

[0040] According to the invention, at least one planetary gear is provided which is arranged to transmit the rotary motion of the axis of the lever element to the generator. Planetary gears, also called epicyclic gears in the prior art, are gears or friction gear systems which, in addition to a fixed axis, also have an axis which rotates in a circular orbit around a fixed frame. A distinction is therefore made between a central or sun gear which is mounted on a fixed axis and an orbiting planet or star gear which is mounted on a rotating axis. The star gear which rotates on its rotating axis orbits the central gear in the same way that the planets orbit the sun. The carrier which holds the rotating axis itself rotates around a fixed axis. Suitable planetary gears and in particular suitable materials for planetary gears used according to the invention, for example stainless steel, are known in the art. Planetary gears are compactly designed gears which have the special feature that their fixed axes (or axes for torque transmission) are aligned with each other. Planetary gears are therefore particularly advantageous for the converter according to the invention.

[0041] In a preferred embodiment, the planetary gear system used in the present invention comprises at least one ring gear (acting as a central gear) as well as several planetary gears, the rotation axes of which are parallel to the rotation axis of the ring gear, the planetary gears being supported by a carrier. The planetary gears preferably rotate around an (inner) sun gear, which shares the rotation axis of the ring gear and is parallel to the rotation axis of the planetary gears. According to the present invention, the planetary gear system is preferably operated in a so-called two-shaft mode, in particular as a stationary transmission, i.e. the carrier is stationary and fixed in place, and both central gear axes, in other words the ring gear and the sun gear, rotate. Preferably, the planetary gears and the (inner) sun gear are arranged within the ring gear. This arrangement allows a very compact design of the planetary gear system. Typically there are 2 to 4 planetary gears, in particular 3 planetary gears per ring gear. The sizing is preferably such that the planetary gear system converts the rotational motion of the ring gear into the faster rotation of the sun gear with a gear ratio of approximately 1:4 to 1:10, especially 1:5 to 1:8.

[0042] The generator is preferably arranged and configured such that the force (energy) transmitted by the planetary gear system is converted into electrical energy. It is further preferred that the planetary gear system, preferably its ring gear, is coupled to the shaft of the lever element, in particular directly between the shaft of the lever element and the generator. It is also preferred that the shaft of the lever element is connected to the ring gear or preferably integrally formed as the ring gear. The shaft of the planetary gear is typically fixed, i.e. it is directly or indirectly connected to the frame. The sun gear is preferably directly connected to the generator drive shaft or even integrally formed as the generator drive shaft. Through this arrangement, a preferred embodiment is made possible in which the planetary gear system converts the rotational movement of the shaft of the lever element into a faster rotation directed towards the generator, preferably with a gear ratio of approximately 1:4 to 1:10, in particular 1:5 to 1:8. In a particularly preferred embodiment, the planetary gear system is substantially integrated into a ring gear on the axis or intermediate shaft of the lever element, which means that the planetary gear and the sun gear are preferably substantially housed in a ring gear, which is part of the axis or intermediate shaft of the corresponding lever element. Preferably, the coupling elements of the mechanical coupling element system extend through the ring gear. This allows for a very compact design of the mechanical coupling element system as well as the gearbox for the generator. In this case, the generator is preferably arranged immediately after the planetary gear system, i.e. adjacent to it, in particular on the side opposite the axis of the lever element.

[0043] The rotor of the generator is typically moved or driven via a mechanical coupling element system and a planetary gear, and the stator of the generator is connected to the support element / rim of the wheel. As explained above, the carrier of the planetary gear, which supports the axis of the planetary gear, preferably forms the stationary part of the planetary gear. And the axis of the sun gear corresponds to the axis on which the rotor of the generator is arranged.

[0044] All generators of the converter are preferably driven simultaneously in a coupled manner by mechanical coupling elements, which preferably means that all generators are driven via corresponding planetary gears arranged on the axes of corresponding lever elements, the axes of the lever elements being in frictional connection via the mechanical coupling element system, in which case a ring gear of the planetary gear system preferably forms part of the mechanical coupling element system, the coupling element in particular running through the ring gear.

[0045] Alternatively, the rotor of the generator is driven via a direct coupling to the intermediate shaft, e.g. a connecting element mounted or coupled thereto, e.g. a connecting wheel, and the stator of the generator is connected to a support element / rim of the wheel. In this embodiment, the force of the lever element is simultaneously transmitted through the mechanical coupling element system to all intermediate shafts and via these to the generators, preferably all generators, thus driving them.

[0046] In order that the generator can still be driven at a suitable speed, even with, for example, a relatively small displacement of the lever element and thus a small movement of the mechanical coupling element system, the converter has a planetary gear system. If appropriate, there may further be a gearbox or transmission, preferably per generator, configured to provide an additional defined transmission between the planetary gear system and the rotational movement of the rotor of the generator. For example, the gearbox and / or transmission is configured to provide a transmission between the planetary gear system and the rotational movement of the rotor towards higher speeds of the rotor, in particular a transmission with a ratio greater than 1 to 1:4, preferably 1:2 to 1:3. However, it is preferred that there is no additional gearbox for the generator apart from the planetary gear system.

[0047] To ensure an uninterrupted movement and thus a power transmission of the mechanical coupling element, it is preferred that the lever element transmits a force to the axis of the lever element, for example via a freewheel clutch, i.e. a clutch that depends on the direction of rotation. The converter therefore preferably has one freewheel clutch per lever element, which is configured for coupling depending on the direction of rotation, i.e. for having a coupling direction and a freewheeling direction for providing an operational coupling. Typically, the freewheel clutch is configured such that a frictional connection occurs when the lever element moves towards the rotation axis of the wheel, and correspondingly, freewheeling occurs when the lever element moves away from the rotation axis of the wheel. The lever element, the freewheel clutch, the mechanical coupling element system, the planetary gear system and the generator are preferably arranged and configured such that the rotational movement of the lever element is transmitted in a coupling direction via the mechanical coupling element system to the rotor of the generator via the freewheel clutch and converted into electrical energy.

[0048] According to a further preferred embodiment, the converter according to the invention has biasing means for the lever element, in particular a spring, which biases the rotation of the lever element around its first end with a force in the rotational movement of the lever element caused by the deformation of the wheel tire due to contact with the road surface, i.e. in the direction of rotation of the lever element towards the axis of rotation of the wheel. The biasing element ensures that the lever element is not in contact with the wheel tire when the wheel is stationary or when the wheel is simply moving at a low speed, i.e. that the lever element remains in a "retracted" state. The latter makes it easier to repair the wheel and to replace the tire on the wheel. The biasing means are therefore suitably configured so that from a suitable rotational speed of the wheel, a movement of the lever element away from the axis of rotation of the wheel is permitted (so that the centrifugal force exceeds the biasing force) and the contact element of the lever element can come into contact with the wheel tire. The biasing means are preferably configured so that from a rotational speed of the wheel of at least 100 rpm, more preferably at least 120 rpm, a movement of the lever element away from the axis of rotation of the wheel is permitted. A typical rotational speed is around 125 rpm, which corresponds to a speed of around 15 km / h (in a car).

[0049] To prevent the forces acting on the lever element from damaging the converter or its components due to excessive impacts and / or excessive deformation of the wheel tread, corresponding protection mechanisms, in particular overload protection devices, are preferably provided. Preferably, the freewheel clutch, the clutch in or to the mechanical coupling element and / or the clutch to the generator are safety clutches with overload protection, thereby allowing rotation without effective coupling if a defined maximum force is exceeded.

[0050] The invention further relates to a system for harvesting electrical energy in a rolling wheel of a vehicle from deformations of the wheel tire due to contact with the road surface, comprising a converter as described above and a support element / wheel rim as a support structure. In one preferred embodiment, the lever element including the contact element does not protrude above the rim flange, i.e. above the outer surface of the cylinder defined by the rim flange.

[0051] In one embodiment, the system comprises a converter as described above as well as a support structure, the support structure typically being configured to hold the energy converter in a fixed arrangement around the central axis of the wheel. In particular, the support structure is itself designed as or integrated into the rim of the wheel, or the system comprises a rim (specially provided to be combined with the support structure) configured to receive the support structure in a fixed manner. The rim is preferably designed in one piece.

[0052] According to a further embodiment, the system has a multi-component rim that can simplify the installation of the transducer or support structure in the wheel. For example, the multi-component rim is designed as a two-component rim with a rim well and a rim sleeve, or as a three-component rim with a rim well, a rim sleeve, and a rim star. In this case, the transducer or support structure and the multi-component rim are configured, for example, such that the transducer or support structure is mounted on the rim well of the multi-component rim.

[0053] Finally, the invention relates to a land vehicle, preferably a car or lorry, or a wheel, comprising a system as described above. In one embodiment, the wheel also comprises a rim motor.

[0054] The invention will now be described on the basis of the drawings. [Brief description of the drawings]

[0055] [Figure 1]FIG. 2 is a perspective view of a transducer according to the invention having a lever element and a mechanical coupling element system on the rim. [Diagram 2] FIG. 2 is a perspective view of a transducer according to the invention having a lever element and a mechanical coupling element system on the rim. [Diagram 3] FIG. 2 is a perspective view of a mechanical coupling element system including a planetary gear system of a converter according to the present invention. [Figure 4] A perspective view of a planetary gear (A) within the shaft gear and a planetary gear (C) outside the shaft gear. [Diagram 5] FIG. 1 is a perspective view through the axis (B) of a lever element without a planetary gear. [Figure 6] FIG. 2 is a schematic side view of a transducer according to the invention having a lever element and a mechanical coupling element system on a rim. [Figure 7] FIG. 2 is a cross-sectional view of a converter according to the present invention having a lever element, a mechanical coupling element system, a planetary gear system, and a generator. [Figure 8] FIG. 2 is a perspective cross-sectional view of a lever element shaft, a mechanical coupling element system, a planetary gear system, and a generator. [Figure 9] FIG. 2 is a perspective view of a lever element including a contact element. [Figure 10] FIG. 2 is a perspective view of a lever element including a contact element. [Figure 11] A diagram illustrating the ratio of the distance of the rotation axis N of the lever element from the wheel center M and the contact point K. [Figure 12] 1A-1C are diagrams illustrating three embodiments of a lever element. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0056] A transducer according to the invention is shown in FIG. 1, comprising a lever element 1 with a contact element 2, in this case a roller, and a mechanical coupling element system 4. The transducer is mounted on a rim 7. The deformation of the tire due to contact with the road surface (not shown) causes the lever element 1, which is located against the inside of the tire in the area of ​​contact with the road surface via the contact element, to rotate at its first end around the rotation axis of the lever element, and thus partially around the axis of the lever element. The lever element 1 performs a "rocking motion" during operation. The restoring force that returns the lever to the "extended" position after passing through the deformation section of the tire caused by its compression is generated by the centrifugal force due to the rotation of the wheel. The lever elements 1 are mounted on their axles via a freewheel clutch, which ensures that the axles rotate only in one direction, specifically when the lever elements are pushed towards the rotation axis of the wheel. Such axle rotation also rotates the drive rollers 18. The generated forces are transmitted from the drive rollers 18 through the coupling system 4, in particular via the respective toothed belts 5, to the neighbouring rollers. Each drive roller 18, together with a neighbouring roller, preferably carries two toothed belts, creating a "closed loop", meaning that every axis of the lever element is frictionally connected to the adjacent axis of the lever element around the wheel through the mechanical coupling element system 4 using the respective coupling element 5. The three generators 6 are mounted on a planetary gear system which is accordingly integrated into the drive roller 18 (not visible). The lever elements 1 and the generators 6 are arranged rotationally symmetrically around the rotation axis of the wheel to avoid wheel imbalance. Due to the movement of a single lever element 1, all drive rollers 18 are rotated, thus driving all three generators 6.

[0057] Figure 2 is similar to figure 1 but shows a transducer according to the invention in which the lever element 1 is shown in a retracted state, in other words folded against the rim 7, due to the limited effect of centrifugal forces, for example when the wheel is stationary or only rotating slowly. When centrifugal forces have little influence, such as when the wheel is stationary or only rotating slowly, a return element (not shown), for example a return spring, causes the lever element to fold inwards, allowing for example to avoid damage when changing a tire on the rim or driving over uneven terrain such as curbs.

[0058] FIG. 3 shows a mechanical coupling element system 4, including a drive roller 18 located on the axis 9 of the lever element, and a corresponding coupling element 5, here implemented as a toothed belt. There are three embodiments of the axis 9 and the corresponding drive roller 18: A, B and C. In the embodiment A of the axis, a planetary gear system 11 is provided inside the drive roller 18. A generator (not shown) is driven via a generator shaft 17, which also forms the axis of the sun gear of the planetary gear system. The embodiment C of the axis corresponds to the embodiment A of the axis, but without the planetary gear system 11, since typically not all the drive rollers 18, for example only every fourth one, are provided with a generator. Typically, as shown in the embodiment B of the axis, every other drive roller 18 is instead equipped with a planetary gear, and is fitted with means for mounting and possibly even tensioning the coupling element 5, in this case a toothed belt, when they are installed.

[0059] FIG. 4 shows a detail of the drive roller 18, located on the axis 9 of the lever element, in embodiments A and C, as illustrated in FIG. 3. In an alternative embodiment of the converter according to the invention, the axis also corresponds to an intermediate axis 10, which does not carry a lever element. In embodiment A of the axis, the planetary gear system 11 is provided inside the drive roller 18. A generator (not shown) is driven via a generator axis 17, which also forms the axis of the sun gear of the planetary gear system. Inside the roller 18, a ring gear 19 of the planetary gear system is rigidly connected to the roller 18, which may also form the ring gear 19 of the planetary gear system. The axis of the planet gear 20 is fixedly arranged on the carrier 22. The axis of the sun gear 21 of the planetary gear system is formed (integrally) as the generator drive axis 17. Embodiment C of the axis corresponds to embodiment A of the axis, but without the planetary gear system 11, since typically only every fourth drive roller 18 is equipped with a generator.

[0060] FIG. 5 shows a detail of the drive roller 18 located on the axis 9 of the lever element, in embodiment B, as also illustrated in FIG. 3. Instead of a planetary gear system, the roller 18 is equipped with means for mounting and possibly even tensioning the coupling element 5, in this case a toothed belt, during their installation. For this purpose, the roller is preferably designed in two parts. The first part of the roller 18 carries the coupling element 5, in this case designed as a toothed belt. The second part is mounted separately on the first part of the roller, and possibly also on the axis 9, such that the second part is preferably added after the coupling element 5 has been installed on the first part of the roller 18. The second part of the roller 18 also carries the coupling element 5, in this case designed as a toothed belt. Preferably, the arrangement of the rollers 18 in the converter alternates around the wheel, with embodiments A and C alternating and embodiment B located between them. Therefore, every other roller is of embodiment B and is equipped with means for mounting and possibly even tensioning the coupling elements (5), in this case the toothed belts, during their installation. This configuration allows easy handling and proper tensioning of the toothed belts on the drive rollers 18 of the converter according to the invention.

[0061] FIG. 6 shows a side view of a converter according to the invention, as shown in FIG. 2, including a contact element 2, in this case a roller, a lever element 1, and a mechanical coupling element system 4. The lever elements are shown in a retracted state, which means that they are folded against the rim 7, for example due to the limited influence of centrifugal forces when the wheel is stationary or rotating at low speed. Also depicted is the mechanical coupling element system 4, including a drive roller 18 and a corresponding coupling element 5, in this case designed as a toothed belt. The lever element 1 and the generator 6 are arranged rotationally symmetrically around the rim 7 in order to avoid imbalance of the wheel. The angle α spanned by the axes of two adjacent lever elements 1 relative to the rotation axis of the wheel is 360° / number of lever elements, in this case 360° / 12=30°.

[0062] Figure 7 shows a cross section AA as shown in Figure 6, through the rim 7 and the converter according to the invention. The lever element 1 is mounted on the shaft 9 via a freewheel clutch 3. This clutch transmits the rotational movement generated by the rocking motion of the lever element to a drive roller 18 and to a corresponding coupling element 5, designed in this case as a toothed belt. The rotation is increased in speed by a planetary gear system 11 and transmitted to the generator drive shaft 17 on the rotor 23 of the generator 6.

[0063] FIG. 8 shows a section AA as shown in FIG. 6, through the rim 7 and the converter according to the invention in a perspective view. The shaft 9 transmits the rotary motion generated by the rocking motion of the lever element to the drive roller 18 and to the corresponding coupling element 5, which in this case is designed as a toothed belt. The rotation is increased in speed by the planetary gear system 11 and transmitted to the generator drive shaft 17 of the generator 6. Inside the drive roller 18, the planetary gear system 11 is provided for this purpose. Inside the roller 18, the ring gear 19 of the planetary gear is rigidly connected to the roller 18, which may itself form the ring gear 19 of the planetary gear system. The shaft of the planet gear 20 is fixedly arranged in the carrier 22. The shaft of the sun gear 21 of the planetary gear system is formed (integrally) as the generator drive shaft 17. This shaft carries the rotor 23 of the generator. The stator 24 of the generator is connected to the rim 7.

[0064] 9 shows a detailed view of an embodiment of a lever element 1 with a contact element 2, in this case designed as a roller. The force is transmitted at a first end of the lever element 1 via an axle 9 to a drive roller 18. The drive roller transmits the force to a mechanical coupling element (not shown). A freewheel clutch 3 transmits the movement of the lever element in only one direction of rotation, and an overload protection device 12 ensures that excessive forces are not transmitted.

[0065] Figure 10 shows a detailed view of an embodiment of a lever element 1 with a contact element 2, in this case designed as a roller. The force is transmitted at a first end of the lever element 1 via an axis 9 to a drive roller 18. The drive roller then transmits the force to a mechanical coupling element (not shown). A freewheel clutch 3 transmits the movement of the lever element in only one direction of rotation, and an overload protection device 12 ensures that excessive forces are not transmitted. A spring is used as a biasing element 13.

[0066] FIG. 11 illustrates length A as the distance of the fulcrum N of the lever element from the wheel center M, and length B as the distance of the fulcrum N of the lever element from the contact point K. The latter is the maximum distance of the contact element from the fulcrum N of the lever element that contacts or can contact the inside of the wheel tire.

[0067] Figure 12 shows details of three embodiments of a lever element 1 with a contact element 2, in this case designed as a roller. In embodiment A, the lever element 1 supports a roller as contact element 2. In embodiment B, the lever element 1 supports a slide 14 (second part) which supports two rollers as contact elements 2. In embodiment C, the lever element 1 also supports a slide 14 (second part) which supports two rollers as contact elements 2. In embodiment C, the two rollers as contact elements 2 are surrounded by a belt 15 which is also guided over another roller (not shown) mounted on the slide. [Explanation of symbols]

[0068] 1 Lever element 2 Contact elements 3 Freewheel Clutch 4. Mechanical coupling element system 5. Joint elements 6. Generator 7 Rims 8 Tires 9 Lever element shaft 10 Intermediate shaft 11 Planetary Gear System 12 Overload protection devices 13. Actuation elements 14 Slides 15 Belt on contact element 16 Deflection roller 17 Generator drive shaft 18 Drive roller 19 Planetary Gear System Ring Gear 20 Planetary Gear System Planet Gear 21 Planetary Gear System Sun Gear 22 Planetary gear system carrier 23 Generator rotor 24 Generator stator

Claims

1. A converter for obtaining electrical energy within a rolling wheel of a vehicle from the deformation of the wheel tire caused by contact with the road surface, a) At least four lever elements (1), wherein at their first ends they are rotatably housed, and at their second ends they are configured to contact the inside of the wheel tire via at least one contact element (2) such that deformation of the wheel tire due to contact with the road surface causes rotational motion of the lever elements, b) A mechanical coupling element system (4) suitable for transmitting the force generated due to the rotational motion of the lever element (1), c) comprising at least one generator (6) configured to convert the force transmitted by the mechanical coupling element system (4) into electrical energy, Here, each lever element (1) is pivotably mounted on its first end by a shaft (9), and the shaft (9) is configured to transmit rotational force. Each mechanical coupling element system (4) per axis (9) of a lever element (1) has at least two coupling elements (5) each arranged to transmit the force of rotational motion to the axis (9) of an adjacent lever element (1) or to an intermediate axis (10), The converter is characterized by the presence of at least one planetary gear system (11) arranged to transmit the rotational motion of the axis (9) or intermediate axis (10) of the lever element to a generator (6).

2. The converter according to claim 1, characterized in that the generator (6) is configured to convert the force transmitted by the planetary gear system into electrical energy.

3. The transducer according to claim 1, characterized in that the planetary gear system is preferably arranged with a gear ratio of approximately 1:4 to 1:10 to convert the rotational motion of the shaft (9) into a faster rotation directed toward the generator.

4. The transducer according to any one of claims 1 to 3, characterized in that the coupling element (5) in the coupling element system (4) is arranged such that the coupling element (5) brings about frictional connection of the axes (9) of all lever elements (1), possibly via an intermediate axis (10).

5. The converter according to any one of claims 1 to 3, characterized in that each coupling element (5) is arranged in a pair in a rotationally symmetrical manner around the rotation axis of the wheel.

6. The converter according to any one of claims 1 to 3, characterized in that the coupling element (5) includes a chain or a belt, in particular a toothed belt.

7. The converter according to any one of claims 1 to 3, characterized in that the lever element (1) is arranged rotationally symmetrically around the rotation axis of the wheel.

8. The converter according to any one of claims 1 to 3, characterized by having at least two generators (6) arranged rotationally symmetrically around the rotation axis of the wheel.

9. The transducer according to any one of claims 1 to 3, characterized in that the lever element (1) transmits force to the shaft (9) via a freewheel clutch (3).

10. The converter according to any one of claims 1 to 3, characterized in that the sum of the distance A from the wheel center M to the pivot point N of the lever element (1) and the contact point K of the contact element with the inside of the wheel tire, provided that if there are multiple contact elements per lever element, the distance B from the contact point having the greatest distance from the pivot point N to the pivot point N is within the range of ((A+B) / R) of 102% to 110% with respect to the radius R on the inside of the wheel tire.

11. The transducer according to any one of claims 1 to 3, wherein at the second end of the lever element (1), the contact element (2) is rotatably housed in the lever element around a rotation axis such that the contact element (2) establishes contact between the lever element and the wheel tire, the rotation axis of the contact element (2) extends substantially parallel to the rotation axis of the wheel, and the contact element (2) has a substantially rotationally symmetric shape with respect to rotation about its pivot point, and in particular corresponds to a roller.

12. The transducer according to any one of claims 1 to 3, characterized in that the contact element (2) is freely rotated about its pivot point with respect to rotation.

13. The converter according to any one of claims 1 to 3, further comprising a biasing means for a lever element (1) that biases the rotation of the lever element (1) around a first end using the force in the rotational motion of the lever element caused by the deformation of the wheel tire due to contact with the road surface.

14. A system for obtaining electrical energy within a rolling wheel of a vehicle from the deformation of a wheel tire caused by contact with the road surface, the system comprising a converter according to any one of claims 1 to 3, and a wheel rim as a support structure.

15. A vehicle or wheel comprising the system described in claim 14.

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