AIRCRAFT WITH PROPULSION PROPELLERS POSITIONED UNDER THE WINGS

Abstract

The present invention relates to an aircraft 1 suitable for vertical flight and horizontal flight, wherein the aircraft 1 has a transport cabin 9 and two wings 3, 4 each arranged on the transport cabin (9), wherein each of the two wings 3, 4 has a first and a second wing part 5, 6, 7, 8, each of the wing parts 5, 6, 7, 8 is designed to be pivotable about a respective pivot axis 31, 32 relative to the remaining wing 3, 4, in particular by up to 90 degrees, each of the wing parts 5, 6, 7, 8 has at least one propeller 2 which is mounted in the wing part 5, 6, 7, 8 so as to be rotatable about a rotation axis and which is arranged with respect to the pivot axis 31, 32 opposite at least a major part 15, 16 of the wing part 5, 6, 7, 8, wherein the propeller 2 is arranged substantially perpendicular to a profile chord of the wing part 5, 6, 7, 8, a propeller motor designed to rotate the propeller 2,and a first gear 33 for the operative connection between the propeller 2 and the propeller motor, wherein the first wing part 5, 6 of the respective wing 3, 4 can be pivoted out such that, in the pivoted-out state, the propeller 2 of the first wing part 5, 6 is located above the wing 3, 4, the second wing part 7, 8 of the respective wing 3, 4 can be pivoted out such that, in the pivoted-out state, the propeller 2 of the second wing part 7, 8 is located below the wing 3, 4, and each of the wings 3, 4 has at least one pivoting means 12, wherein a pivoting out and / or a resetting of the pivoting out of the first and / or second wing part 5, 6, 7, 8 can be provided by means of the at least one pivoting means 12.

Description

Field of the invention

[0001] The present invention relates to an aircraft suitable for vertical flight and horizontal flight. Background of the invention

[0002] The aircraft shown in the disclosures DE202017006138U1, DE202019000936U1, DE202019002731U1, and EP21210288.3 have so-called "tilt wings" (i.e., wing sections that can be tilted) and "tilt rotors" (i.e., propellers) attached to them, which enables a meaningful separation of climbing (vertical) and speed flight (horizontal). In the prior art aircraft, for vertical flight (vertical takeoff), all wing sections are tilted by approximately 90 degrees from their horizontal position so that all propellers are above the wings. The air currents generated by the rotation of the propellers therefore flow toward the ground, creating a lift force on the respective propeller that is directed vertically upwards, i.e., away from the ground.

[0003] If all propellers are arranged above the wings during vertical flight, as in the current technology, and then aligned forward (for the front propellers) and rearward (for the rear propellers) for horizontal flight, it is necessary, depending on the direction of flight, for either the front propellers or the rear propellers, to either reverse the direction of rotation of the corresponding propeller rotors or change the blade pitch of the corresponding propeller rotors. Otherwise, the airflows caused by the rotation of the front propeller rotors would flow in the opposite direction to the airflows caused by the rotation of the rear propeller rotors. Such opposing airflows would, among other things, cause the aircraft to rotate in circles during horizontal flight instead of moving in the desired direction.

[0004] However, reversing the direction of rotation of the propeller rotors or changing the blade pitch angle of the propeller rotors must be carried out precisely, quickly, and at a coordinated time. This in turn requires an additional, powerful control unit that precisely controls the corresponding steps. This makes the transition from vertical to horizontal flight a complex and safety-relevant undertaking for state-of-the-art aircraft. If the reversal of the direction of rotation or the change in the blade pitch angle of the propeller rotors is not controlled with sufficient precision by the control unit (e.g. due to a fault in the control unit ora malfunction in one of the control processes), the propeller rotors may, for example, remain stationary for too long or the drive force may not be optimally directed, which in turn may lead to a loss of performance in the acceleration of the aircraft, to turbulence such as rotation, rolling, lurching or jerking movements, to an unplanned and sudden descent of the aircraft and / or, in the worst case, even to a crash of the aircraft. Object of the invention

[0005] It is therefore an object of the invention to provide an aircraft which overcomes the disadvantages of the prior art, particularly in light of simplicity and efficiency.

[0006] A further task is to provide an aircraft that enables a simplified transition from vertical flight to horizontal flight or vice versa.

[0007] Another task is to provide an aircraft with a more efficient and longer-lasting propulsion system.

[0008] These objects are achieved by implementing at least some of the characterizing features of the independent claims. Features that further develop the invention in an alternative or advantageous manner can be found in some of the remaining features of the independent claims and the dependent claims. Summary of the invention

[0009] The invention relates to an aircraft suitable for vertical flight and horizontal flight, wherein the aircraft has a transport cabin, in particular a passenger cabin, and two wings each arranged on the transport cabin, in particular on a roof of the transport cabin, wherein each of the two wings has a first and a second wing part, each of the wing parts is fixed relative to the remaining wing ("remaining wing" equals "wing" minus "wing parts"), in particular by up to 90 degrees, and is designed to be pivotable about a respective pivot axis, each of the wing parts has ∘ at least one propeller which is mounted in the wing part so as to be rotatable about a rotation axis and which, with respect to the pivot axis, is arranged opposite at least a large part of the wing part, wherein the propeller is substantially perpendicular to a profile chord of the wing part, ∘ a propeller motor designed to rotate the propeller, and ∘ a first gear for the operative connection between the propeller and the propeller motor, wherein the first wing part of the respective wing is pivotable in such a way,that in the swung-out state the propeller of the first wing part is located above the wing, the second wing part of the respective wing can be swung out in such a way that in the swung-out state the propeller of the second wing part is located below the wing, and each of the wings has at least one pivoting means, wherein by means of the at least one pivoting means a pivoting out and / or a resetting of the pivoting out of the first and / or the second wing part can be provided.

[0010] The aircraft according to the invention has, compared to aircraft of the prior art, the advantage that, due to the presence of the propeller of the respective second wing section below the respective wing, during the transition from vertical flight (take-off) to horizontal flight on reversing the direction of rotation of the propeller rotors of the respective first wing section or the respective second wing section (depending on which wing section provides the front propeller and which the rear propeller and depending on the direction of flight), or changing the blade pitch angle of the propeller rotors and thus reversing the direction of the driving force (or lift) of the corresponding propeller, for example by means of a pitch control, can be dispensed with.

[0011] Due to the inventive arrangement of the respective second wing part below the respective wing, as soon as the position of the wing parts and thus of the propellers for horizontal flight has been assumed, the air flows caused by the rotation of the propeller rotors of the front propellers are directed in the same direction as the air flows caused by the rotation of the propeller rotors of the rear propellers.

[0012] The aircraft according to the invention can therefore move in a targeted manner in the direction of flight without reversing the direction of rotation or changing the blade pitch angle of the propeller rotors of the respective first wing section or the respective second wing section, thus eliminating the need for a powerful control unit intended for precisely controlling the reversal of the direction of rotation or the change in the blade pitch angle, as well as corresponding complex control processes. Consequently, the aircraft according to the invention has, on the one hand, a generally simplified structure and, on the other hand, a simplified transition from vertical to horizontal flight, which is a major advantage over the prior art, especially with regard to efficiency and simplicity.

[0013] In particular, because a control unit and corresponding complex control processes can be dispensed with, the transition from vertical to horizontal flight in the aircraft according to the invention is less susceptible to failure. This is of great importance with regard to flight safety, since a malfunction (e.g., an inaccuracy or even a complete failure of the control) during this step can have significant consequences, as already described. Furthermore, since the airflows caused by the propellers already flow as desired and thus no undesirable movements of the aircraft occur during the transition from vertical to horizontal flight, further complex flight stabilization measures, which in turn necessitate further complicated control systems, are unnecessary.

[0014] In an exemplary embodiment of the aircraft according to the invention, the at least one pivoting means is designed as a chain drive, wherein the chain drive has a first sprocket and a second sprocket, wherein a movement of a chain of the chain drive can be provided by means of a (rotary) movement of the first sprocket, wherein the second sprocket can be driven by means of the movement of the chain of the chain drive, wherein the pivoting out and / or the resetting of the pivoting out (pivoting in) of the first and / or the second wing part can be provided by means of the driven second sprocket.

[0015] This embodiment of the aircraft according to the invention has, among other things, the advantage over aircraft of the prior art that the pivoting means can be designed very simply and in a space-saving manner.

[0016] In a further exemplary embodiment of the aircraft according to the invention, each of the wings has at least one stepper motor designed to drive at least one pivoting means (or chain drive), and / or at least one second drive battery designed to supply the at least one stepper motor with electrical energy, wherein the second drive battery is arranged in or on the wing in such a way that it is replaceable and / or rechargeable there, in particular, wherein at least one second gear is arranged for the operative connection between the at least one stepper motor and at least one pivoting means (or chain drive).

[0017] In other words, the first sprocket of the chain drive can be driven by a stepper motor, which in turn is operatively connected to a second gear, whereby the (rotational) movement of the first sprocket also sets the chain guided over the first sprocket in motion. The chain is guided over the second sprocket, which is arranged at the level of the pivot axis of the corresponding wing section, and thus transfers its kinetic energy to the second sprocket, which is also set in (rotational) motion. The second sprocket then transfers its kinetic energy to a (drive) shaft arranged on the second sprocket, which in turn ensures that the corresponding wing section pivots out or in.

[0018] In a further exemplary embodiment, the first gear and / or the second gear is an eccentric gear, in particular a double eccentric gear.

[0019] In a further exemplary embodiment, the respective eccentric gear has an internal toothing with a tooth difference in the range of 0 to 5 teeth, in particular of one tooth, in particular wherein a tooth shape of the teeth of the respective eccentric gear is such that the respective eccentric gear has an oval toothing.

[0020] These embodiments have the advantage that, since an eccentric gear, in particular a double eccentric gear, has low friction losses, increased longevity, increased stability even at high speeds, a suitable reduction ratio, etc., the aircraft according to the invention, in particular with regard to the first gear, has an efficient and low-wear (and thus longer-lasting) drive.

[0021] Furthermore, eccentric gears enable the transmission of high (torque) torques and high reduction ratios with a compact design and minimal backlash, thus ensuring high precision over the entire service life (e.g., hysteresis loss of 0.5 to max. 1 arcmin). This high level of precision also has the side effect of keeping transmission errors in the gear extremely low. This keeps the input speed very constant. The two-stage reduction principle of a double eccentric gear ensures excellent dynamic performance and smooth running, as well as high repeatability and path accuracy. The gear absorbs axial and radial loads and bending moments and contributes to high torsional rigidity as well as resistance to shock and overload. In emergency stop situations, the eccentric gears can absorb up to 500% of the rated torque.This is particularly important for aircraft, as a failure of the propeller gear during flight due to a defect can lead to the aircraft crashing.

[0022] Due to the previously described design of the second gear, in particular as a (double) eccentric gear, the transmission of a high rotational and holding torque to the first sprocket of the first chain drive or to the first sprocket of the second chain drive is possible, whereby the respective first sprocket can perform a controlled, step-by-step (rotational) movement.

[0023] The second gear can be configured such that both positive and negative (torque) moments can be transmitted to the first sprocket of the chain drive via the second gear. The corresponding torque is transmitted via the chain of the chain drive to the second sprocket and thus (e.g., via a corresponding (drive) shaft) to the corresponding wing part. Thus, by means of the pivoting means configured as a chain drive, both the outward pivoting movement, which has, for example, a positive torque, and the inward pivoting movement, which accordingly has, for example, a negative torque, can be executed.

[0024] In an exemplary embodiment of the aircraft according to the invention, the first sprocket of the chain drive has a smaller diameter than the second sprocket of the chain drive, in particular wherein the diameter of the first sprocket is smaller by a factor of 2 to 4 than the diameter of the second sprocket.

[0025] The design of the first sprocket with a smaller diameter or a smaller surface than the second sprocket allows the pivoting means, designed as a chain drive, to generate an increased torque and holding moment on the second sprocket, whereby this increased torque is transmitted to the respective wing part via the (drive) shaft arranged on the second sprocket, and thus the pivoting out or pivoting in of the respective wing part takes place with a large torque and holding moment. Such a large torque and holding moment when pivoting out or pivoting in of the respective wing part is advantageous because it allows the pivoting out or pivoting in movement to be carried out gradually (i.e.that the swivelling or swivelling movement is stopped once a desired angle of inclination / tilt angle has been reached and the position of the corresponding wing section can be held at this angle of inclination) reliably and with the desired precision (e.g. with regard to the tilt angle) and speed. Especially at higher flight speeds, enormous wind pressure acts on the respective wing section, which could impair or even prevent its swivelling or swivelling movement if the torque generated by the corresponding swivelling means (here the chain drive) when swivelling or swivelling in the respective wing section were too low. Furthermore, if the holding torque was too low, the wing sections could be pushed out of their set angular position by the wind pressure, which would significantly impair the flight characteristics of the aircraft.

[0026] In an exemplary embodiment of the aircraft according to the invention, each of the two wings has a first pivoting means and a second pivoting means, wherein the first pivoting means can be used to provide the outward pivoting and / or the resetting of the outward pivoting (or also the inward pivoting) of the first wing part of the respective wing and the second pivoting means can be used to provide the outward pivoting and / or the resetting of the outward pivoting (or also the inward pivoting) of the second wing part of the respective wing.

[0027] In a further exemplary embodiment of the aircraft according to the invention, the first pivoting means of the respective wing is designed as a first chain drive and the second pivoting means of the respective wing is designed as a second chain drive.

[0028] In these embodiments, the first wing part and the second wing part of a respective wing can be pivoted out or back into the pivoted (or folded) position independently of one another. Furthermore, the respective wing part can be pivoted out or in stepwise to a desired inclination angle / tilt angle and held at this angular position, which, for example, deviates from the horizontal and vertical angular positions.

[0029] The first sprocket of the first chain drive and the first sprocket of the second chain drive can each be driven by a stepper motor, which in turn is operatively connected to a second gear. In an alternative embodiment, the first sprocket of the first chain drive and the first sprocket of the second chain drive can be driven by a single stepper motor, which in turn is operatively connected to only a second gear. This second gear can be switched to drive either the first sprocket of the first chain drive or the first sprocket of the second chain drive.

[0030] It goes without saying that the first and / or second sprocket do not necessarily have to be circular. In principle, any shape (e.g., even a polygonal or rectangular shape) for the corresponding sprocket is possible; ultimately, it is only a matter of setting the chain in motion by means of a (rotary) movement of the first sprocket and thus transferring the torque to the second sprocket. Furthermore, a rope or a rod construction can be used instead of the chain, for example; ultimately, it is only a matter of transferring the torque from the first sprocket to the second sprocket. For this purpose, it would also be possible to design the first and second sprockets as a single piece; it is only important that the torque generated by the stepper motor and transmitted by the second gear can be transferred to the (drive) shaft, which provides the outward or inward pivoting of the respective wing section.Furthermore, the (respective) pivoting mechanism does not necessarily have to be a chain drive. Designs are also possible in which the pivoting mechanism is a cable or chain hoist, with one end of the cable or chain of the cable or chain hoist being attached to the corresponding wing section and the other end of the cable or chain being attached to a (cable) winch arranged on the wing. By winding or unwinding the cable or chain, the corresponding wing section can then be pivoted in or out.

[0031] The aircraft according to the invention solves, among other things, the technical problem of enabling a simpler, more efficient, and less failure-prone transition from vertical flight to horizontal flight compared to the prior art. Furthermore, the first and / or second gears can be designed as durable and efficient (double) eccentric gears, thereby enabling more efficient and durable drives.

[0032] In an exemplary embodiment of the aircraft according to the invention, each of the wing parts has at least one first drive battery designed to supply the propeller motor with electrical energy, wherein the first drive battery is arranged in or on the wing part such that it is replaceable and / or rechargeable there, a communication unit designed to receive control signals, in particular control signals from an external transmission source, a control unit designed, in each case as a function of the control signals, to control a pivot angle of the wing part and to control the rotation of the propeller, and / or at least one photovoltaic cell arranged on a surface of the wing part, which is connected to the first drive battery and is designed to charge the first drive battery.

[0033] This design has the advantage of allowing for decentralization of the propulsion batteries. Instead of a single, large electrical power source for the four propellers, the propulsion battery is distributed among them, reducing the energy density of the entire aircraft and thus minimizing the risk of overheating.

[0034] In another exemplary embodiment, the two wings arranged on the transport cabin, in particular on the roof of the transport cabin, are formed as a single piece. This single-piece wing can, for example, be placed on the roof from above and secured there. Alternatively, the two wings can also be connected to the roof of the transport cabin on the left and right sides in such a way that the single-piece wing forms the roof of the transport cabin.

[0035] In a further exemplary embodiment, the first wing part is arranged in a front region and the second wing part is arranged in a rear region of the respective wing.

[0036] This embodiment has the advantage that when transitioning from vertical flight to horizontal flight according to the "normal" flight direction intended for the aircraft, no reversal of the direction of rotation or change of the blade pitch angle of the propeller rotors of the respective second wing section is necessary.

[0037] In a further exemplary embodiment, each of the wing parts is designed to be substantially semicircular, so that pivoting out of the respective wing part results in a semicircular recess in the remaining wing, and / or each of the wing parts has a cell structure in its interior to increase rigidity, wherein the first drive battery is arranged in a cell of the cell structure.

[0038] In a further exemplary embodiment, the aircraft according to the invention further comprises an air cooling circuit, in particular with at least one fan, wherein the air cooling circuit is arranged to cool at least one of: the first drive battery, the second drive battery, the propeller motor, the control unit and the at least one stepper motor, in particular wherein the first and / or second drive battery is designed to supply the at least one fan with electrical energy, and / or a transmitting unit arranged in the transport cabin, wherein the communication unit is designed to receive control signals from the transmitting unit, in particular wherein the transmitting unit is designed to receive at least one of: control signals, anti-collision system warning signals, weather information signals, navigation signals from an external transmitting source.

[0039] In a further exemplary embodiment, the transport cabin has a supply battery and the remaining wing has on its surface at least one photovoltaic cell which is connected to the supply battery and is designed to charge the supply battery.

[0040] In a further exemplary embodiment, the first drive battery, the second drive battery, and / or the supply battery designed as a solid-state battery, rechargeable by an external energy source (e.g. suitable charging stations), in particular via a cable, wherein the charging of the corresponding battery takes place while the corresponding battery is still installed in the aircraft or the battery is at least temporarily removed from the aircraft, and / or as soon as the corresponding battery is discharged (empty), replaceable by a corresponding charged (full) battery.

[0041] In a further exemplary embodiment, each of the wings has a contact protection device designed to to be arranged on an underside of the wing, to provide a, in particular semicircular, protective wall around the propeller of the second wing part which is present below the wing in the swung-out state, and to shield the propeller from physical contact from an area outside the contact protection by means of the protective wall.

[0042] In a further exemplary embodiment, the aircraft has two auxiliary wings, wherein one of the two auxiliary wings is arranged on a longitudinal side, in particular on a lower region of the longitudinal side, of the transport cabin, wherein the two auxiliary wings are designed to generate a counter-torque proportional to the speed, by means of which an air resistance of the aircraft, increased in particular by the transport cabin and / or the contact protection, can be compensated, whereby a pitching movement of a front of the aircraft, in particular during horizontal flight, can be prevented and thus a stabilization of the flight characteristics of the aircraft can be achieved.

[0043] In a further exemplary embodiment, at least one of the following parts of the aircraft Transport cabin, wing, first wing section, second wing section, propeller, propeller motor, first gearbox, second gearbox, swivel means, auxiliary wing, or contact protection, at least predominantly made of at least one lightweight material, in particular carbon, preferably glass fiber reinforced carbon, Kevlar, titanium and / or aluminum.

[0044] In another exemplary embodiment the major part of the first wing part lying opposite the propeller is designed in such a way that said major part, in a swung-out state (i.e. during vertical flight), forms a first base for the aircraft (comparable to the landing skids of a helicopter), in particular wherein the first base is formed at least approximately at a first end of the transport cabin, and / or (since the second wing part of the aircraft swings out in the opposite direction and standing on the propeller of the second wing part would impair the functionality of the aircraft) the transport cabin has a second (separate) base, in particular on a floor of the transport cabin, in particular wherein the second base is arranged at least approximately at a second end of the transport cabin opposite the first end of the transport cabin.

[0045] In other words, the invention relates to a universal aircraft ("universal" because it can fly vertically and horizontally) with an electric drive and tilting wings, wherein each tilting wing has its own traction system consisting of a propeller blade, eccentric gear, electric motor, pivoting means (e.g., chain drive), traction battery, power electronics, and hinge-like tilt joints. This traction system can be controlled via radio from the cockpit and / or from the ground. In other words, in some embodiments, the electric drive motors for the propellers and the elements for adjusting the pivotable, semicircular wing sections are at least largely housed in the pivotable wing sections so that, through their weight effect, they generate a stable torque relative to the rotational axis of the tilt rotors.In other words, in some embodiments, the adjustability of the tilt wings of a wing is ensured by two chain drives arranged in or on the wing, over whose respective first and second chain wheels (or chain sprockets) a respective chain is guided. The respective first chain wheels are rotated by one (or two) electric stepper motor(s) with a high holding torque, so that the respective tilt angle of the tilt wings can be accurately adjusted. In contrast to the fixed position of the engines in a purely fixed-wing aircraft, here the angle of climb of the wings can be determined by the adjustable engines and controlled with great force. Therefore, there is no need for the tail units required at the rear of fixed-wing aircraft. In particular, for the required torque of the relatively large propellers, with a diameter of approximately 3 meters, at low speeds, an eccentric gear with, for example,a total gear ratio of i = 36 and a high-speed DC motor with over 25,000 rpm in the tilting wing. With four propellers, for example, the total power is 100 kW and the total weight is approximately 900 kg.

[0046] For cooling the motors and the eccentric gears, air cooling (or an air cooling circuit) is provided. The air flows occurring during the aircraft's movement run past the wings and the first and second wing sections (tilt wings) and accordingly cool their surfaces / outsides. By cooling these surfaces, the propeller motors and the eccentric gears, which are arranged on or within the wing sections, are simultaneously cooled and can transfer their heat to the surrounding (cooled) parts by means of convection heat flow and thus do not overheat. Furthermore, structures (e.g.Ventilation shafts) can be provided through which the air flows that occur can be at least partially guided, in particular wherein the structures can be arranged in such a way that the air flows guided therein are directed to the propeller motors and / or the eccentric gears (and from the propeller motors and / or the eccentric gears back out) and these can be cooled by the air cooling circuit provided in this way. The structures for directing the air flows can also be arranged within the parts of the aircraft in such a way that the air flows can be directed into the transport cabin (and from the transport cabin back out), whereby the transport cabin can be cooled by the air cooling circuit provided in this way, for example to a comfortable room temperature for the passengers or to a significantly lower temperature for refrigerated goods.

[0047] For the transport of air within the structures, suitable fans (or ventilators) can be used, whose electric motors can be supplied with electrical energy from the first drive battery, the second drive battery, and / or the supply battery.

[0048] In further embodiments, a metallic coating is applied to the outer skin of at least one of the propellers, the transport cabin, the wing sections, and the remaining wing. This coating prevents electrostatic charging and lightning strikes (Faraday cage) and ice formation. In further embodiments, a gyrocompass in the transport cabin provides a flight attitude indicator for pitch and roll, as well as an airspeed indicator. In further embodiments, a display for the status (e.g., charge level, temperature) of the traction battery is provided in the cockpit. Brief description of the drawings

[0049] The aircraft according to the invention is described in more detail below using exemplary embodiments schematically illustrated in the figures. Identical elements are identified by the same reference numerals in the figures. The described embodiments are generally not drawn to scale and are not to be understood as limiting. In detail, Fig. 1 : perspective view of an exemplary embodiment of the aircraft according to the invention; Fig. 2 : View of an exemplary embodiment of the aircraft according to the invention from above; Fig. 3 : Side view of an exemplary embodiment of the aircraft according to the invention; Fig. 4A-4C : schematic representation of an exemplary embodiment of the first transmission; Fig. 5A-5C : schematic representation of an exemplary embodiment of the second transmission, Fig. 6: View of the arrangement of an exemplary embodiment of the pivoting means on the wing. Detailed description of the drawings

[0050] Figure 1shows a perspective view from above of the entire aircraft 1 with the four propellers 2 (also called tilt rotors), with the wings (wings) 3, 4 extending on both sides of the transport cabin 9 and with the first wing sections (semicircular tilt wings) 5, 6 and the second wing sections (semicircular tilt wings) 7, 8. In the embodiment shown, the transport cabin 9 is designed as a passenger cabin, which is particularly designed to accommodate at least one person, preferably two or more people. If appropriate radio control is provided, a human pilot can be dispensed with under certain circumstances, allowing another passenger to be transported. In particular, equipped with a longitudinally and transversely operating gyrocompass, an altimeter and a satellite-controlled navigation system, such a universal aircraft can be operated completely autonomously.On the other hand, at least based on a navigation system (e.g., GPS), a pilot in aircraft 1 can be shown approximately how far the target position remains. A pre-warning (e.g., "Target reached in 4 km or 2 min") can alert the pilot. The wing sections 5-8 are each mounted on a hinge-like joint 10 in one of the fixed (remaining) wings 3, 4, pivoting by up to 90 degrees. Their task is to transfer the forces of the rotor propellers 2 to the rest of the system, including the passenger cabin 9. These joints 10 must be highly load-bearing, largely wear-free, and operate reliably for many years with very little frictional resistance. Therefore, they are preferably equipped with roller bearings, especially space-saving needle bearings. They can be lubricated with a lifetime grease filling.The adjustment of the tilt wings (wing sections) 5, 6, 7, 8 is each achieved by a pivoting means 12, here the chain drive 12, which functions in a known manner with a first chain wheel 54 and a second chain wheel 55. An electric stepper motor 56, which is operated either from the cockpit or automatically, serves to actuate each chain drive 12. This respective stepper motor 56 can also have a respective reduction gear 46 (also referred to as a second gear 46), for example an eccentric gear, in particular a double eccentric gear. The adjustment of a respective wing section 5-8 by means of such a chain drive 12 represents an ideal solution, since it allows the enormous gyroscopic forces of the high-speed propeller motors to be overcome and the desired tilt angle to be accurately set.

[0051] Figure 2shows the aircraft 1 from above, with the first tilt wings 5, 6 fully swung out for vertical flight, thus pointing the front propellers 2 upwards, and the second tilt wings 7, 8 fully swung out for vertical flight, thus pointing the rear propellers 2 downwards. The complete swung out exposes semicircular recesses or openings 11 in the remaining wings 3, 4.

[0052] Figure 3shows a side view of an exemplary embodiment of the aircraft 1 according to the invention. For horizontal flight, the first and second chain drives 12 have the wing parts 5, 7 (6, 8 not shown here) retracted flush (drawn with solid lines). The first wing part 5 is pivoted out for vertical takeoff / vertical flight so that the propeller 2 rotates above the wing 3, while the opposite large part 15 of the first wing part 5 is located below the wing 3 (drawn with dashed lines). For the second wing part 7, the situation is exactly the opposite, with the propeller 2 rotating below the wing 3 and the opposite large part 16 of the wing part 7 being located above the wing 3. Furthermore, the embodiment of the aircraft 1 shown has an auxiliary wing 17 and a contact guard 18.The auxiliary wing 17 is arranged in a lower region on the side of the transport cabin 9, i.e., in a lower region of the longitudinal side of the transport cabin 9. The auxiliary wing 17 ensures that, particularly during horizontal flight, a speed-proportional counter-torque is generated, by means of which an increased air resistance of the aircraft 1, in particular due to the transport cabin 9 and / or the contact protection 18, is compensated, thereby preventing a pitching movement of a front 19 of the aircraft 1, particularly during horizontal flight, and thus stabilizing the flight characteristics of the aircraft 1. The contact protection 18 is arranged on the underside of the wing 3 and, starting therefrom, extends with a support structure / mounting approximately as far towards the ground as the second wing part 7.At the end of the holder of the contact guard 18 facing the ground, a protective wall is arranged which extends horizontally, in particular in a semicircle, around the propeller 2 of the second wing part 7 which, in the swung-out state, is located below the wing 3 (the contact guard thus has a shape comparable to the letter L when viewed from the side), which shields the propeller 2 from physical contact from an area outside the contact guard 18, among other things in order to enable passengers to board and disembark safely.

[0053] In the embodiment shown, the major part 15 of the first wing section 5, which is opposite the propeller 2, is designed such that, in the swung-out state (i.e., for vertical flight), it serves as a base (comparable to the landing skids of a helicopter). Since the second wing section 7 of the aircraft 1 swung in the opposite direction and standing on the propeller 2 of the second wing section 7 would impair the functionality of the aircraft 1, the transport cabin 9 has a separate base 20 at the end where the second wing section 7 is located (i.e., at the rear of the aircraft 1 in the embodiment shown). Since weight reduction plays a major role, especially in aircraft, in order to ensure flight capability on the one hand and to optimize energy efficiency during flight on the other (e.g.,due to a reduced weight of the aircraft, the fuel consumption is also reduced), the above-mentioned components in an exemplary embodiment of the aircraft 1 shown can be designed at least predominantly from at least one lightweight material, in particular carbon, preferably glass fiber reinforced carbon, Kevlar, titanium and / or aluminum.

[0054] In particular, when the corresponding components of the aircraft 1 are designed from lightweight materials and battery-operated electric motors are used as propeller motors and / or stepper motors, the corresponding embodiment of the aircraft 1 according to the invention has, among other things, the following further advantages over aircraft from the prior art: Reduced overall weight (e.g. through designing components from lightweight materials), Increased efficiency (e.g. improved energy transfer from the propeller motors to the propellers through the use of efficient, low-wear and low-friction, long-lasting double eccentric gears), Increased flight speed (e.g. through improved transmission or reduction ratios in the first gear designed as a double eccentric gear), Greater range (e.g. through reduced energy consumption due to the reduced weight and / or the efficient gears), Reduction of emissions (e.g. through the use of electric motors (purely electric operation) and / or the generally reduced energy consumption), Improved flight characteristics / flight stability (e.g. through the auxiliary wings that prevent pitching movements, etc. of the aircraft), Simplified construction (e.g.by the fact that the swivel mechanism can be designed as a space-saving chain drive, that a separate control unit, which would have to control a reversal of the direction of rotation or a change in the blade pitch angle of the propellers of the second wing sections (e.g. via a pitch control), can be dispensed with, and / or that a rotatable bearing of the rotor blades in the rotor hub for the pitch control can be dispensed with), Low-noise operation (e.g. through the use of electric motors), Less maintenance-intensive (e.g. through durable double eccentric gears and / or the simplified replacement of empty or broken batteries due to the easy accessibility of the batteries), More environmentally friendly operation (e.g. through reduced fuel consumption, quieter operation, reduced emissions, etc.), and Increased safety (e.g.because the batteries are arranged decentrally and / or a reversal of the direction of rotation or a change in the blade pitch of the propellers of the second wing sections is no longer necessary, which means that on the one hand there is no need for a brief interruption of the driving forces of these propellers and on the other hand there is no need for an additional and at the same time failure-prone control unit).

[0055] The transition from vertical to horizontal flight is undoubtedly the most complex and, in terms of flight safety, the most critical phase of such an aircraft. Here, the aerodynamic forces are divided into those from the propeller rotors and those from the fixed wings. At the same time, they are divided into vertical and horizontal force components. Furthermore, the airflows have different speed directions, so the aerodynamic forces are no longer clearly defined. Therefore, these conditions are determined in advance on the wind tunnel test bench and taken into account when controlling the aircraft.

[0056] The Figure 3The arrows show the directions of the air flows occurring during horizontal and vertical flight and the corresponding forces acting. During vertical flight, the propeller 2 of the first wing section 5, which rotates above the wing 3, has a direction of rotation (for example, clockwise) such that the air flow 21 is directed towards the ground 22. The lift force 23 in this propeller acts against the air flow 21, i.e. in a direction away from the ground 22. The propeller 2 of the second wing section 7, which rotates below the wing 4, has the same direction of rotation (for example, also clockwise), so that the air flow 24 is also directed towards the ground 22, which is why the lift force 25 in this propeller 2 also acts in a direction away from the ground 22.Because the two lift forces 23 and 25 each point vertically upwards (away from the ground 22), a vertical takeoff of the aircraft 1 is enabled. Because the propeller 2 of the second wing section 7 in the aircraft 1 according to the invention rotates below the wing 3, during the transition from vertical flight to horizontal flight and accordingly when the first and second wing sections 5, 7 pivot, the air flows 21 and 24 continue to flow in the same direction (opposite the direction of flight 26), which is why the drive forces (propulsion) 27 and 28 in both propellers 2 also act in the same direction (in the direction of flight 26). Consequently, a reversal of the direction of rotation or a change in the blade pitch angle (e.g., by means of a pitch control) of the propeller 2 of the second wing section 7 in the aircraft 1 according to the invention is no longer necessary.This enables a simplified and, at the same time, less prone to failure transition from vertical flight to horizontal flight and vice versa compared to state-of-the-art aircraft. Due to the shape of the wing 3 and / or the auxiliary wing 17, the aircraft 1 experiences a respective lift force 29, 30 from the corresponding wings even during horizontal flight, which acts vertically upwards (away from the ground 22) and thus enables the aircraft 1 to continue climbing even during horizontal flight.

[0057] The Figures 4A to 4Ceach show a schematic representation of an exemplary embodiment of the first gear 33, which in the embodiment shown is designed as a double eccentric gear. For reasons of weight reduction, the first gear 33 designed as a double eccentric gear in an exemplary embodiment can be made at least predominantly from at least one lightweight material, in particular carbon, preferably glass fiber reinforced carbon, Kevlar, titanium and / or aluminum. In the exemplary embodiment shown, the double eccentric gear 33 has an internal toothing with a tooth difference of one tooth. In the Figure 4AIn the secondary part 34 of the double eccentric gear 33 shown, the ring gear 35 has twenty teeth, wherein the individual teeth each have a height of 5 to 10 millimeters, in particular 7 millimeters, and starting from the pivot point 36 there is an angle of 18 degrees between each two teeth. The cycloid disc 37 of the secondary part 34 (e.g. made of glass fiber reinforced carbon) has 19 teeth 50 on its outer edge, wherein the individual teeth 50 each have a height of 5 to 10 millimeters, in particular 7 millimeters, which engage on one side 38 in the recesses 51 of the ring gear 35 and come to rest on the teeth 50 of the ring gear 35 on the opposite side 39. The cycloidal disc 37 (also cycloplate) further has an internal toothing of five, with the four teeth 52 of the pinion 40 engaging in the corresponding recesses 53 on the inside of the cycloidal disc 37.The teeth 52 of the pinion 40 can be milled from steel, then ground and plasma-nitrided, preferably making them as smooth as possible. A lubricant, e.g., a grease (roller bearing grease), can be introduced into the cavities created by the tooth differences. This lubricant ensures the safe, smooth, and low-wear operation of the double eccentric gear 33. The double eccentric gear 33 shown has oval teeth. Due to the tooth height of 7 millimeters to 10 millimeters in particular, this double eccentric gear 33 is also referred to as a module 7.0 to 10. Furthermore, there is a transmission ratio of 6, which is calculated from the number of teeth of the ring gear 35 and the number of teeth of the pinion 40.

[0058] The Figure 4BThe primary part 41 of the double eccentric gear 33 shown also has a structure corresponding to that of the secondary part 34 (in particular with regard to the number and size of the teeth of the respective components), however the cycloidal disc 42 has six circular cutouts 43 into which six rollers / bolts 44 (also referred to as bearing bolts / cyclo bolts, e.g. made of rolling bearing steel, e.g. 100 Cr 6, with a hardness of at least 60 HRc, induction hardened and ground, iced or glued into the cyclo plate) of a roller disc (as part of the drive shaft) engage (the described arrangement can also be referred to as a rolling bearing). The primary part 41 also has a transmission ratio of 6 and is also made of glass fiber reinforced carbon.Because both the primary part 41 and the secondary part 34 have a gear ratio of 6, the double eccentric gear used as the first gear 33 of the aircraft 1 according to the invention has a total gear ratio of 36. The first gear 33 is operatively connected to the propeller motor (in other words: the power provided by the propeller motor is transmitted via the first gear 33 to the propeller 2, which then rotates the propeller), whereby the propeller motor can be an electric motor, in particular a (double) reluctance motor, e.g., a C. Lungu positive motor. Such a motor has the advantage that no rare earths are required for permanent magnets and that speeds of up to 25,000 revolutions per minute (rpm) are possible. Furthermore, such a motor has a climb power of up to 25 kW and a horizontal power of up to 6.5 kW.

[0059] In Figure 4C1 shows the arrangement of the primary part 41 (also referred to as the primary stage) and the secondary part 34 (also referred to as the secondary stage) in the first gear 33 of the aircraft 1 according to the invention, which is designed as a double eccentric gear. The propeller motor, designed as an electric motor, transfers the kinetic energy it provides (approximately 25,000 rpm) to the primary stage 41, which is then set in motion. Because the primary stage 41 is connected to the secondary stage 34, the kinetic energy is transferred to the secondary stage 34. The secondary stage 34 is in turn connected to the propeller shaft 45 (for example, has five external teeth and is approximately 2 m long), which is also set in motion by the movement of the secondary stage 34 and thus drives the propeller 2. Due to the overall gear ratio of 36, the propeller shaft 45 has a speed of approximately 700 rpm.In other words, due to the eccentricity of the cycloidal disc 37, the propeller shaft 45 performs a wobbling movement with the same eccentricity as the cycloidal disc 37, only on the side of the secondary stage 34.

[0060] The Figures 5A to 5C each show a schematic representation of an exemplary embodiment of the second gear 46 for the operative connection between the stepper motor 56 and the pivoting means 12 (here a chain drive 12), wherein the second gear 46 in the embodiment shown is designed as a double eccentric gear with the primary stage 47 and the secondary stage 48. For reasons of weight reduction, the second gear 46 designed as a double eccentric gear in an exemplary embodiment can also be designed at least predominantly from at least one lightweight material, in particular carbon, preferably glass fiber reinforced carbon, Kevlar, titanium and / or aluminum. Figure 5Ashown secondary part 48 and the one in Figure 5BThe primary part 47 of the double eccentric gear 46 shown is basically designed in the same way as the primary part 41 of the double eccentric gear 33, particularly with regard to the number and size of the teeth, the tooth difference, the materials of the respective components and the transmission ratio, wherein in the embodiment shown, six bolts 49 (also referred to as bearing bolts / cyclo bolts, e.g. made of rolling bearing steel, e.g. 100 Cr 6, with a hardness of at least 60 HRc, induction-hardened, ground, plasma-nitrided and smooth-polished) of a roller disc engage in the secondary part 48. However, unlike the double eccentric gear 33, which is connected to the propeller shaft 45, this roller disc is not connected to a drive shaft, but is designed as part of the first chain wheel 54 (also referred to as chain drum 54) of the chain output 12, which is designed to move a chain 13, 14 by means of a rotary movement.In another embodiment of the double eccentric gear 46 shown, the secondary part 48 can be connected to the drive shaft 57, which is also set in motion by the movement of the secondary part and thus drives the first sprocket 54 of the chain output 12.

[0061] The second gear 46 is operatively connected to the stepper motor 56 (in other words: the force provided by the stepper motor 56 is transmitted via the second gear 46 to the first sprocket 54 of the chain drive 12, causing the sprocket to rotate and set the chain 13, 14 in motion), wherein the stepper motor 56 can be an electric motor, in particular a (double) reluctance motor, e.g., a C. Lungu positive motor. Because both the primary part 47 and the secondary part 48 also have a gear ratio of six, the double eccentric gear used as the second gear 46 of the aircraft 1 according to the invention has a total gear ratio of 36, just like the first gear 33.

[0062] In Figure 5C1 shows the arrangement of the primary part 47 (also referred to as the primary stage) and the secondary part 48 (also referred to as the secondary stage) in the second gear 46, designed as a double eccentric gear, of the aircraft 1 according to the invention. The stepper motor 56, designed as an electric motor, transfers the kinetic energy it provides to the primary stage 47 (approx. 1500 rpm), which is then set in motion. Because the primary stage 47 is connected to the secondary stage 48, the kinetic energy is transferred to the secondary stage 48. The secondary stage 48 is in turn connected to the first sprocket 54 (or chain drum 54) (or to the drive shaft 57, which in turn is connected to the first sprocket 54), which is set in rotation by the movement of the secondary stage 48 and thus sets the chain 13, 14 in motion. Due to the total gear ratio of 36, the first sprocket 54 has a speed of approx.42 rpm.

[0063] In Figure 6The arrangement of an exemplary embodiment of the first pivoting means 12, designed for pivoting out or in the first wing part 5 of the wing 4, and of the second pivoting means 12, designed for pivoting out or in the second wing part 7 of the wing 4, on the wing 4 is shown. The first pivoting means is designed as a first chain drive 12 and the second pivoting means as a second chain drive 12, wherein the first and second chain drives 12 each have a first sprocket 54 and a second sprocket 55, wherein in the embodiment shown, the diameter of the first sprocket 54 is smaller than the diameter of the second sprocket 55.The respective stepper motor 56, designed as an electric motor, is operatively connected to a respective second gear 46, which in turn transmits the energy provided by the respective stepper motor 56 to the respective drive shaft 57, which in turn sets the respective first sprocket 54 in motion. The movement of the respective first sprocket 54 drives the respective chain 13, 14, which in turn sets the respective second sprocket 55 in motion. The respective second sprocket 55 is connected to the respective shaft 58, which is also set in a rotary movement by the rotary movement of the respective second sprocket 55 and thus causes the tilt movement of the wing part 5, 7.

[0064] It is understood that these figures only schematically illustrate possible embodiments. The various approaches can also be combined with each other and with prior art methods.

Claims

1. Aircraft (1) suitable for vertical flight and horizontal flight, wherein the aircraft (1) has a transport cabin (9), in particular a passenger cabin, and two wings (3, 4) each arranged on the transport cabin (9), in particular on a roof of the transport cabin (9), wherein • each of the two wings (3, 4) has a first and a second wing part (5, 6, 7, 8), • each of the wing parts (5, 6, 7, 8) is designed to be pivotable about a respective pivot axis relative to the remaining wing (3, 4), in particular by up to 90 degrees, • each of the wing parts (5, 6, 7, 8) has ∘ at least one propeller (2) which is mounted in the wing part (5, 6, 7, 8) so as to be rotatable about a rotation axis and which, with respect to the pivot axis (31, 32), is pivotable relative to at least a major part (15, 16) of the wing part (5, 6, 7, 8), wherein the propeller (2) is arranged substantially perpendicular to a profile chord of the wing part (5, 6, 7,8), ∘ a propeller motor designed to rotate the propeller (2), and ∘ a first gear (33) for the operative connection between the propeller (2) and the propeller motor, , characterized in that • the first wing part (5, 6) of the respective wing (3, 4) can be pivoted out in such a way that, in the pivoted-out state, the propeller (2) of the first wing part (5, 6) is located above the wing (3, 4), • the second wing part (7, 8) of the respective wing (3, 4) can be pivoted out in such a way that, in the pivoted-out state, the propeller (2) of the second wing part (7, 8) is located below the wing (3, 4), and • each of the wings (3, 4) has at least one pivoting means (12), wherein a pivoting out and / or a resetting of the pivoting out of the first and / or the second wing part (5, 6, 7, 8) can be provided by means of the at least one pivoting means (12).

2. Aircraft (1) according to claim 1, wherein the at least one pivoting means (12) is designed as a chain drive, wherein the chain drive (12) has a first chain wheel (54) and a second chain wheel (55), wherein a movement of a chain (13, 14) of the chain drive (12) can be provided by means of a movement of the first chain wheel (54), wherein the second chain wheel (55) can be driven by means of the movement of the chain (13, 14) of the chain drive (12), wherein the pivoting out and / or the resetting of the pivoting out of the first and / or the second wing part (5, 6, 7, 8) can be provided by means of the driven second chain wheel (55).

3. Aircraft (1) according to claim 1 or 2, wherein each of the wings (3, 4) has • at least one stepper motor (56) designed to drive at least one pivoting means (12), and / or • at least one second drive battery designed to supply the at least one stepper motor (56) with electrical energy, wherein the second drive battery is arranged in or on the wing (3, 4) such that it is replaceable and / or rechargeable there, in particular wherein at least one second gear (46) is arranged for the operative connection between the at least one stepper motor (56) and at least one pivoting means (12).

4. Aircraft (1) according to one of the preceding claims, wherein the first gear (33) and / or the second gear (46) is an eccentric gear, in particular a double eccentric gear.

5. Aircraft (1) according to claim 4, wherein the respective eccentric gear (33, 46) has an internal toothing with a tooth difference in the range of 0 to 5 teeth, in particular of one tooth, in particular wherein a tooth shape of the teeth of the respective eccentric gear (33, 46) is such that the respective eccentric gear (33, 46) has an oval toothing.

6. Aircraft (1) according to claim 2 and one of claims 3 to 5, wherein the first sprocket (54) of the chain drive (12) has a smaller diameter than the second sprocket (55) of the chain drive (12), in particular wherein the diameter of the first sprocket (54) is smaller by a factor of 2 to 4 than the diameter of the second sprocket (55).

7. Aircraft (1) according to one of the preceding claims, wherein each of the two wings (3, 4) has a first pivoting means (12) and a second pivoting means (12), wherein the first pivoting means (12) can be used to pivot out and / or return the pivoting out of the first wing part (5, 6) of the respective wing (3, 4) and the second pivoting means (12) can be used to pivot out and / or return the pivoting out of the second wing part (7, 8) of the respective wing (3, 4).

8. Aircraft (1) according to one of the preceding claims, wherein each of the wing parts (5, 6, 7, 8) has • at least one first drive battery designed to supply the propeller motor with electrical energy, wherein the first drive battery is arranged in or on the wing part (5, 6, 7, 8) such that it is replaceable and / or rechargeable there, • a communication unit designed to receive control signals, in particular control signals from an external transmission source, • a control unit designed, in each case as a function of the control signals, to control a pivot angle of the wing part (5, 6, 7, 8) and to control the rotation of the propeller (2), and / or • at least one photovoltaic cell arranged on a surface of the wing part (5, 6, 7, 8), which is connected to the first drive battery and is designed to charge the first drive battery.

9. Aircraft (1) according to one of the preceding claims, wherein the first wing part (5, 6) is arranged in a front region (19) and the second wing part (7, 8) is arranged in a rear region of the respective wing (3, 4).

10. Aircraft (1) according to one of the preceding claims, further comprising • an air cooling circuit, in particular with at least one fan, wherein the air cooling circuit is arranged to cool at least one of: the first drive battery, the second drive battery, the propeller motor, the control unit and the at least one stepper motor, in particular wherein the first and / or second drive battery is designed to supply the at least one fan with electrical energy, and / or • a transmitting unit arranged in the transport cabin (9), wherein the communication unit is designed to receive control signals from the transmitting unit, in particular wherein the transmitting unit is designed to receive at least one of: control signals, anti-collision system warning signals, weather information signals, navigation signals from an external transmitting source.

11. Aircraft (1) according to one of the preceding claims, wherein the transport cabin (9) has a supply battery and wherein the remaining wing (3, 4) has on its surface at least one photovoltaic cell which is connected to the supply battery and is designed to charge the supply battery.

12. Aircraft (1) according to one of the preceding claims, wherein each of the wings (3, 4) has a contact guard (18) designed to • be arranged on an underside of the wing (3, 4), • provide a, in particular semicircular, protective wall around the propeller (2) of the second wing part (7, 8) present below the wing (3, 4) in the swung-out state, and • shield the propeller (2) from physical contact from an area outside the contact guard (18) by means of the protective wall.

13. Aircraft (1) according to one of the preceding claims, wherein the aircraft (1) has two auxiliary wings (17), wherein one of the two auxiliary wings (17) is arranged on a longitudinal side, in particular on a lower region of the longitudinal side, of the transport cabin (9), wherein the two auxiliary wings (17) are designed to generate a counter-torque proportional to the speed, by means of which an air resistance of the aircraft (1), increased in particular by the transport cabin (9) and / or the contact protection (18), can be compensated, whereby a pitching movement of a front (19) of the aircraft (1), in particular during horizontal flight, can be prevented and thus a stabilization of the flight characteristics of the aircraft (1) can be achieved.

14. Aircraft (1) according to one of the preceding claims, wherein at least one of the following parts of the aircraft (1) • transport cabin (9), • wing (3, 4), • first wing part (5, 6), • second wing part (7, 8), • propeller (2), • propeller motor, • first gear (33), • second gear (46), • pivoting means (12), • auxiliary wing (17), or • contact protection (18), is at least predominantly made of at least one lightweight material, in particular carbon, Kevlar, titanium or aluminum.

15. Aircraft (1) according to one of the preceding claims, wherein • the major part (15) of the first wing part (5, 6) lying opposite the propeller (2) is designed such that said major part (15) forms a first stand for the aircraft (1) in a pivoted-out state, in particular wherein the first stand is formed at least approximately at a first end of the transport cabin (9), and / or • the transport cabin (9), in particular on a floor of the transport cabin (9), has a second stand (20), in particular wherein the second stand (20) is arranged at least approximately at a second end of the transport cabin (9) opposite the first end of the transport cabin (9).