FR3133370A1 - secure bucket-chassis of paramotor with birotor propulsion exported rear lateral - Google Patents

Abstract

Motorized paragliding propeller propulsion assembly comprising, a wing, hangers, a harness (2) mounted on a rigid chassis (3) which carries a pilot (1) positioned in front of the chassis (3) and creating behind him a zone of turbulence (6) characterized in that two propellers are operated directly by two identical electric motors powered by a battery, controlled by an electronic flight controller, rotating in opposite directions and are maintained in the same vertical plane offset by a rear offset at the rear of the chassis (3) and offset laterally by two lateral offset arms anchored by a central connection at the rear of the chassis (3) so that the air flow processed by the propellers is not impacted by the turbulence zone (6). Figure for abstract: Fig. 1

Description

secure bucket-chassis of paramotor with birotor propulsion exported rear lateral

Technical area.

The present invention relates to a secure bucket-chassis for a paramotor with exported rear lateral birotor propulsion. A paramotor is an ULM type aircraft, acronym for Ultra Light Motorized, which is a motorized paraglider which can take off in the plain, maintain itself and evolve in the air thanks to engine thrust. A paramotor uses a flexible paraglider-type wing, connected to a chassis by two carabiners, the engine is mounted on this same chassis. Piloting is done with two brake handles which act on the wing, and with a throttle handle which activates the thermal engine.

The invention aims to improve the propulsion of paramotors by means of a new improved chassis which allows working with two engines.

State of the prior art.

Indeed, the propulsion of ULM type aircraft has historically been achieved using a single engine and a single propeller of the traction or propulsive type for reasons of mass limitation, simplicity of design and costs. A propeller located at the rear of the machine is a propulsion configuration. It creates thrust thanks to a motorized propulsion unit located at the rear of the machine. This concerns ULMs of the tilting, paramotor or autogyro type.

This propulsion has numerous defects that the invention aims to correct.

A first fault is that the propulsive thrust is in the flow of the pilot harness. This position with the plane of the propulsive propeller downwind of an obstacle generates aerodynamic disturbances. These disturbances are all the greater when the propeller plane is close to the obstacle.

A second fault comes from the effects of the engine torque of a single propeller. The engine torque is felt permanently when the propeller rotates and increases with the propeller rotation speed. A single propeller configuration also forms a gyroscope. Torque, gyroscopic effect and gyroscopic precession will degrade flight maneuverability and aeronautical performance.

The prior art has attempted to provide a response to these defects by proposing twin-rotor paramotors. For the moment, the answers are not satisfactory.

For example, there is patent DE102015120680 which proposes two counter-rotating propellers mounted at both ends of a transverse horizontal arm upstream of the pilot. The device concerns the connection between a connecting bar of the two engines mounted flexibly at the front of the pilot and not at the rear. This is a traction configuration. This configuration has several disadvantages, including a higher noise level for the pilot whose head is very close to the plane of the propellers, reduced flight comfort, an increased risk due to the flexibility of the assembly of collision with a propeller in the event of flight incident or take-off.

Patent IT2012TO00624 is also known, with a propulsion configuration with, at least, 2 laterally offset propellers. The system is foldable and can be deployed in flight. But it is intended to be used on a parachute, and is poorly suited to a paramotor. Indeed, on this technical proposal, it is impossible to take off from the plain in a safe manner due to the total absence of propeller protection. It is also impossible to inflate with the so-called back sail technique, the plane of the propellers being located at the level of the pilot's back, very close to the wing's suspension cone. When turning, the line cone deforms and can collide with one of the 2 propellers. This configuration therefore seems dangerous for the user and unusable in flat flight for a paramotor.

None of the solutions of the prior art therefore provides a satisfactory solution.

Presentation of the invention.

A main object of the invention is to propose a solution which overcomes the defects of the prior art and which is secure for all phases of flight, and for all flight maneuvers.

An object of the invention is to offer the pilot sound comfort, seating comfort, and optimized driving performance.

An object of the invention is to propose a solution which allows easy maneuverability for floor storage, an acceptable weight and a minimum bulk so as to pass through a standard size door to be stored in a room or a vehicle.

An object of the invention is to propose a solution which is economical and which can be industrialized at an acceptable market price.

In a main aspect, the invention proposes an improved chassis which allows a new secure twin-rotor propulsion configuration, with offset lateral rear propulsion.

In one aspect the invention adds protection by a cage system whose plane of rotation is sufficiently far from the lines in all phases of flight.

In one aspect the invention adds electronic regulation of aerodynamic thrust. A multi-propeller configuration comprising at least two offset propellers according to the invention makes it possible to create an asymmetrical thrust. A yaw torque is then created which will improve maneuverability in turns or make it possible to stabilize the device in a straight trajectory when the weather conditions are agitated. This thrust asymmetry is achieved by electronic regulation. Thus, a multi-propeller configuration makes it possible to create assistance in the trajectories of the aircraft.

Detailed description.

The invention will be better understood on reading the detailed figures in which:

represents a general view of the invention in a flight situation in front side perspective view.

represents a perspective view of the bucket-chassis in rear view.

represents a rear perspective view of the propulsion part folded for storage.

represents a view of the propulsion part in side view folded for storage.

represents a general side view of the invention with the rear offset of the propellers.

shows in perspective view the propeller protection system.

represents the disassembled hull profiles in high perspective view.

represents the step of inflating the sail when it is placed on the ground using the so-called back sail method.

represents a detail of the line protection system.

represents the modularity of propeller protection in three different mounting configurations.

represents a principle view of the joystick of the electronic flight controller.

shows an assembly on a cocoon-type harness which improves the aeronautical performance of the aircraft.

And detail this twin-engine configuration. The pilot (1) is installed in a harness (2) mounted at the front on a rigid chassis (3). The propellers (4, 5) are driven directly by two identical electric motors (7, 8) rotating in opposite directions to cancel torque and reduce gyroscopic effects. These two motors are held at the rear of the chassis (3) by a central connection (9) and two lateral offset arms (10, 11), a left arm and a right arm, mounted respectively on two lockable pivots (12, 13). The side shift arms (10, 11) are aerodynamically shaped to promote air flow. The left and right lateral offset arms (10, 11) export the left and right propellers (4, 5) laterally, so that the air flow processed by the propellers is not impacted by the turbulence zone (6). ) which is located behind the pilot's back (1). The lateral offset arms (10, 11) and the central connection (9) are made entirely or partially of lightweight aeronautical quality material such as 7075 aluminum or carbon fiber composites for example. An electric battery (29) supplies the system with energy.

represents a perspective view of the propulsion part in rear view folded for storage and shows how anti-vibration pads (14) make a semi-rigid connection between the chassis (3) and the central connection (9) in order to reduce the vibrations transmitted to the chassis by the rotation of the propellers (4, 5). This figure shows how the assembly is designed to be foldable with the offset arms (10, 11) which are articulated in connection with two lockable pivots (12, 13) mounted on the central connection (9), the propellers (4, 5) are foldable according to their axis of rotation. Also appears, the flight controller (23) which is favorably positioned secured to the chassis near the two electric motors (7, 8).

represents a side view of the propulsion part folded for storage. When unlocked, the locking pivots (12 and 13) are angled such that the two arms (10, 11) fold so that the propellers (4 and 5) are above and below the plane of the thrust vector in order to limit the bulk. The overall width of the propulsion part in folded mode is therefore of the order of magnitude of the width of the chassis (3) and the pilot harness (2). Folding and unfolding is done without tools thanks to pivots (12, 13) with manual locking, safety pinning, for example with Beta pins, can be used.

represents a general side view of the invention in flight with the rear offset (S) of the plane of the propellers with respect to the center of gravity of the pilot, indicated pilot weight (Pp). This rear offset (S) is a safety length between the line cone and the propeller plane. For reasons of mass centering and the lightness of the electric motors, this distance can be greater than on a single propeller paramotor. It can be doubled or more compared to that of a single propeller paramotor. The positioning on the machine in the electric battery chassis strongly defines the position of the center of gravity of the machine and the point of application of the weight of the machine (Pm). The battery must be positioned closest to the pilot's center of gravity (Pp), i.e. close to the pilot's back, and on the lower part of the machine's chassis to facilitate its maneuverability during the takeoff run. . Lift is indicated (P) and applies at the risers.

shows in perspective view the propeller protection system. A protection system prevents the lines and brake controls from being in the path of the propeller (15) in flight but also during the inflation and take-off phases on the ground when the wing is not not yet powered on. Any contact between a rotating propeller and the lines or brake controls destroys the latter or the wing profile. On single propeller paramotors, thermal or electric, an annular cage encompasses the entire propeller. It is necessary to allow inflation using the sail back method. This cage creates additional mass, drag and friction on the lines during the inflation phase using the backsail method, this causes premature wear of the lines. In the case of multi-propeller propulsion, the cage does not need to completely cover the propellers because the risk of collision with the propellers is geometrically reduced. Only the upper and central part of the propellers must be protected. Partial protection of each propeller at approximately 120° angle is sufficient to ensure sufficient protection during all phases of flight. During flight incidents, the risk of collision with the propellers is limited by two geometric aspects. Firstly, the propeller plane of a multi-propeller aircraft is further from the risers and the suspension cone because the propellers are further back from the point of attachment to the wing. Secondly, because the surface swept by the propellers is also offset laterally by the offset arms (10, 11) on either side of the chassis (3), this reduces the risk of collision between the lines and the propellers. Here is therefore represented a cage system that can be dismantled without tools with the propeller scanning plane. A removable cage is made up of at least two long and thin profiled hull elements (16, 17). An upper hull profile (16) in the form of an arc, and a hull profile (17) with a flat radius. These hull profiles are light and flexible in aeronautical quality material, for example aluminum, magnesium, stainless steel, titanium, polymers, wood, or in composite materials, for example glass fibers or carbon fibers. The section of the hull profiles (16, 17) is flat. Their section is thin enough to have sufficient bending along the greatest length and to limit drag and it is wide enough to have sufficient mechanical inertia to counter the force of the lines during a flight incident or takeoff. The hull profiles (16, 17) are held together by a hull assembly part (18) comprising two slots identical to their profile with a functional clearance in which the plates are inserted. The part (18) forms an angle of around 60° between the two hull profiles (16, 17). The assembly part (18) is glued or permanently fixed to one of the two profiles and is held on the other when used with a quick release means, such as a pin (19). Two other slotted parts for attaching the hull to the chassis (20, 21) hold the cage in position during use. These parts are also made up of slots into which the profiles enter with sufficient depth to allow pinning. During assembly, the angles and the tension linked to the deformation by bending of the profiles (16) allow mechanical balance of the cage. The assembled structure is self-supporting without pinning. The pinning has a safety role linked to accelerations and vibrations during use. The profiles can be assembled and dismantled without tools using quick-assembly pins (19) or any other rapid-assembly device without tools. The hull attachment parts (20, 21) are made of polymer, composite or metallic material. Their shapes are aerodynamic and particularly suited to additive manufacturing. The dimensioning of the different elements of the cage is such that, once assembled, the propeller plane cannot exceed the elements of the cage. When it is dismantled, the cage profiles occupy the place of the flat hull profiles (16, 17): the elements of the cage return to a rectilinear shape which greatly facilitates their transport and storage.

represents the hull profiles (16, 17) dismantled in high perspective view. The pins (19) are mounted on the hull assembly part (18), itself mounted glued to the radius profile (17). The hanger holders (22) are not mounted on the 2 hulls (16).

represents the wing inflation stage. The configuration presented above does not directly allow inflation - back - sail - with the lines placed on the ground and the sail lowered behind the machine. In fact, the lines would get stuck either in the propellers (4, 5), under the offset arms (10, 11) or in the engines (7, 8). To allow take-off using the so-called back sail technique, compared to a single propeller paramotor with an annular cage, it is necessary to maintain the lines during back sail inflation. This support must be done at a height close to that of the risers and with an optimum spacing. This spacing is optimal when it deforms the suspension cone of the wing as little as possible when it is placed on the ground behind the pilot. A line holder (22) allows back-sail inflation. It is a V-shaped part which maintains all of the lines during the ground preparation phase and during the first moments of inflation of the wing. The two hanger holders (22) are positioned symmetrically and are adjustable on the ground in spacing by sliding on the profile (16) to adapt as closely as possible to the width of the wing placed on the ground. A set screw or other holding device fixes the position when the correct setting is found. Changing the wing may require re-tuning.

represents a detail of the line protection system and three possible positions, A, B, C of the line holder (22) which can slide on the upper hull profile (16). This part is designed not to degrade the finesse: it is aerodynamic and made or not in the same material and with the same process as the other assembly parts of the cages (18, 20 and 21). The use of these hanger holders (22) allows easier inflation than with a central cage of a single propeller paramotor. In fact, the lines are already located at the same height as the risers and the lines will be less deformed during the inflation phase. The deformation of the line cones during inflation is less significant than with an annular central cage. The lines no longer rub on an annular cage when they are mechanically tensioned. Inflation becomes easier and the lines wear less with each takeoff. We find a sensation close to inflation - back sail - when we take off in a paraglider. If the user wishes to take off using the sail face method then he can dismantle the hanger holders (22) by sliding them along the upper hull profile (16) when the latter is not mounted on the chassis, as shown on the . The hanger holders (22) have no use outside of the canopy inflation phase.

represents the modularity of propeller protection in three different mounting configurations. Indeed ; ULM legislation in certain countries may require an integral cage around the propellers. Each element protects over approximately 120° of angle. Additional cage elements can also be fitted depending on the pilot's inflation experience.

represents the control lever of the electronic flight controller (23) which makes it possible to regulate the power setpoint of each engine. This differential regulation is done according to the flight conditions and in particular the altitude and the angles of evolution of the aircraft. The flight controller (23) has several essential regulation functions: - Maintain the asymmetry of the thrust in phases of flight without change of direction - Create an asymmetric thrust facilitating turning during changes of direction - Limit the angle of pitching - Provide passive safety monitoring of failure of one of the two motors. From a certain configurable safety height, stability regulation can be manually deactivated by the pilot in flight. The regulation then switches to an asymmetric thrust mode regulated according to the yaw, pitch and roll angles to improve maneuverability when cornering. If the asymmetric thrust mode is engaged, from a certain variation in the angles of evolution, the regulator detects a turn and the thrust becomes asymmetric. Engine power on the inside of the turn will be reduced to create yaw torque on the aircraft. Under these conditions, the maneuverability of a 2-axis aircraft is considerably increased and saves energy and improves the maneuverability and autonomy of the machine. The aircraft will turn better with less input on the controls and will therefore cause less degradation of glide ratio when turning. For example, a roll angle of 30° will give a setpoint of 70% to the internal motor at the turn compared to the power of the external motor at the turn. On a paramotor, as on any aircraft, taking too high an angle of attack is of no use and the aircraft will not climb any faster. On a paramotor, if the thrust at the pilot's level is too great, the pilot will move forward in a rocking motion in front of the wing. The wing will pitch up and increase its drag without increasing the rate of climb. There is no aeronautical benefit in exceeding a certain angle of attack and pitch. The electronic regulation maintains an optimum pitch angle and will limit the driving thrust so as not to exceed too large an angle. This angle depends on the characteristics of the wing and the flying weight. It is defined by a software learning program. The program monitors the pitch angle from which the rate of climb begins to stop increasing. This is the optimal operating angle. In the event of an unplanned shutdown of one of the two motors, a safety function of the flight controller (23) is to immediately stop the other motor. This is done by analyzing the evolution of the yaw angle or by comparing the power of each of the engines or by comparing the rotation speeds of each of the engines or by a combination of these 2 or 3 factors. If the change in the yaw angle is too rapid, for example a variation of more than 180° in less than 1 second, or if the difference in power or if the difference in rotation speed between the motors is too great then the other motor is secured. That is to say a complete shutdown of the second motor because the probability of a failure of the first motor is high. During safety, both engines are cut off and the pilot must make an emergency landing.

The sampling of all functions of the flight controller (23) is at least 10 Hz.

Due to the possible control of the yaw, and therefore of the trajectory, by thrust asymmetry, steering by thrust asymmetry is possible. The aircraft can change trajectory by asymmetrically varying thrust without the pilot needing to control traditional controls on a two-axis aircraft. It is a mode of piloting a two-axis aircraft without degradation of finesse and lift. This control mode can be achieved using a wireless control handle (24). This handle is ambidextrous and is held in the pilot's hand during takeoff and flight. It has at least one pusher (25), a bistable push button (26), a control lever (27) and a safety strap (28). The pusher (25) is the accelerator which gives the gas setting. It is operated by pressure between the pilot's fingers and palm. This pusher can move according to a translation or a rotation. When no action is carried out, the pusher (25) returns to the zero point. The flight controller (23) will distribute the gas setpoint to the two engines according to the flight phases. The bistable push button (26) allows you to activate and deactivate the asymmetrical piloting mode by an ON/OFF action of the pilot. The control lever (27) is of the game lever type on an axis of freedom which makes it possible to define the asymmetry of the thrust either by translation or by rotation on its axis of freedom. When no action is performed, the lever (27) returns to the neutral point. If the flight controller (23) is coupled to a GPS type location system, automatic type piloting is possible by automatically and asymmetrically varying the thrusts to follow a predefined GPS trajectory.

This autopilot mode can also provide safety with an automatic return to the takeoff field, for example in the event of a sudden loss of meteorological visibility or a low battery indication, as is the case with recreational drones.

shows an assembly on a cocoon-type harness which improves the aeronautical performance of the aircraft.

Furthermore and not shown herein, there is possibly a man-machine interface produced by at least one visual interface of the LCD type or via software on a smartphone. This interface displays information about the status of the machine, including battery, on the ground and information about the battery status and flight conditions during use. It also allows, for example, to activate autopilot mode.

The present invention therefore relates to a motorized paragliding propeller propulsion assembly comprising, a wing, hangers, a harness (2) mounted on a rigid chassis (3) which carries a pilot (1) positioned in front of the chassis (3) and creating behind it a zone of turbulence (6) characterized in that two propellers (4, 5) are actuated directly by two identical electric motors (7, 8) powered by an electric battery (29), controlled by a flight controller electronic (23), rotating in opposite directions and are maintained in the same vertical plane offset by a rear offset (S) at the rear of the chassis (3) and offset laterally by two lateral offset arms (10, 11) anchored by a central connection (9) at the rear of the chassis (3) so that the air flow treated by the propellers is not impacted by the turbulence zone (6).

The present invention therefore relates to a motorized paragliding propeller propulsion assembly characterized in that anti-vibration pads (14) make a semi-rigid connection between the chassis (3) and the central connection (9) in order to reduce the vibrations transmitted to the chassis by the rotation of the propellers (4, 5).

The present invention therefore relates to a motorized paragliding propeller propulsion assembly characterized in that the assembly is designed foldable with the offset arms (10, 11) which are articulated in connection with two lockable pivots (12, 13) mounted on the central connection (9), the propellers (4, 5) are foldable along their axis of rotation.

The present invention therefore relates to a motorized paragliding propeller propulsion assembly characterized in that a battery (29) is positioned closest to the pilot's center of gravity (Pp), close to the pilot's back, and on the lower part of the machine's chassis to facilitate its maneuverability during the take-off course.

The present invention therefore relates to a motorized paragliding propeller propulsion assembly characterized in that a cage consisting of at least two symmetrical elements consisting of long and thin hull profiles (16, 17), including a hull profile (16) upper in an arc, and a hull profile (17) of flat radius, protect the propellers against collision with a hanger.

The present invention therefore relates to a motorized paragliding propeller propulsion assembly characterized in that a set of hanger doors (22) allows inflation during the ground preparation phase and during the first moments of inflation of the wing, the two hanger holders (22) are V-shaped to hold the hangers inside the V and are positioned symmetrically, they are adjustable on the ground in spacing by sliding on the profile (16) to adapt as closely as possible to the width of the wing placed on the ground.

The present invention therefore relates to a motorized paragliding propeller propulsion assembly characterized in that a pilot joystick comprising an ambidextrous wireless control handle (24), held in the pilot's hand during takeoff and flight, presents at minus a pusher (25), a bistable push button (26), a control lever (27) and a safety strap (28) allows the pilot to regulate the power setpoint of each motor by means of the instruction addressed to the electronic flight controller (23).

The present invention therefore relates to a motorized paragliding propeller propulsion assembly characterized in that the flight controller (23) is coupled to a GPS type location system to create automatic type piloting by automatically and asymmetrically varying the thrusts to follow a predefined GPS path.

Equivalently, the invention can be declined in a two-seater variant where the pilot (1) does not change place, the passenger being placed in front of the pilot in tandem. The wing attachment points are then placed further forward of the machine to balance the paramotor's center of gravity. This two-seater configuration increases the safety distance (S).

Equivalently, the invention can be applied to other light aircraft of the ULM type, two-seater or single-seater, such as trolley-type paramotors, motorized hang gliders or tilting ULMs.

Variants of the invention, by equivalence, are obviously covered herein without departing from the inventive scope.

Claims (9)

Motorized paragliding propeller propulsion assembly comprising a wing, hangers, a harness (2) mounted on a rigid chassis (3) which carries a pilot (1) positioned in front of the chassis (3) and creating a turbulence zone behind him (6) characterized in that two propellers (4, 5) are actuated directly by two identical electric motors (7, 8), powered by a battery (29), controlled by an electronic flight controller (23), rotating in opposite directions and are maintained in the same vertical plane offset by a rear offset (S) at the rear of the chassis (3) and offset laterally by two lateral offset arms (10, 11) anchored by a central connection (9 ) at the rear of the chassis (3) so that the air flow processed by the propellers is not impacted by the turbulence zone (6). Motorized paragliding propeller propulsion assembly according to claim 1 characterized in that anti-vibration pads (14) make a semi-rigid connection between the chassis (3) and the central connection (9) in order to reduce the vibrations transmitted to the chassis by the rotation of the propellers (4, 5). Motorized paragliding propeller propulsion assembly according to claim 1 characterized in that the assembly is designed foldable with the offset arms (10, 11) which are articulated in connection with two lockable pivots (12, 13) mounted on the connector central (9), the propellers (4, 5) are foldable along their axis of rotation. Motorized paragliding propeller propulsion assembly according to claim 1 characterized in that a battery (29) is positioned closest to the pilot's center of gravity (Pp), close to the pilot's back, and on the lower part of the chassis of the machine to facilitate its maneuverability during the take-off course. Motorized paragliding propeller propulsion assembly according to claim 1 characterized in that a cage consisting of at least two symmetrical elements consisting of long and thin hull profiles (16, 17), including an upper hull profile (16) in an arc of circle, and a hull profile (17) of radius, plane, taken in the gripping grooves protect the propellers against the collision of the passage of a hanger. Motorized paragliding propeller propulsion assembly according to claims 1 and 5 characterized in that the propeller protection cage is made with different assemblies of hull profiles (16, 17) each time forming an angle of 120° between them. Motorized paragliding propeller propulsion assembly according to claim 1 characterized in that a set of hanger doors (22) allows inflation during the ground preparation phase and during the first moments of inflation of the wing, both hanger holder (22) are V-shaped to hold the hangers inside the V and are positioned symmetrically, they are adjustable on the ground in spacing by sliding on the profile (16) to adapt as much as possible to the width of the wing placed on the ground. Motorized paragliding propeller propulsion assembly according to claim 1 characterized in that a pilot joystick comprising an ambidextrous wireless control handle (24), held in the pilot's hand during take-off and flight, has at least one push button (25), a bistable push button (26), a control lever (27) and a safety strap (28) allows the pilot to regulate the power setpoint of each motor by means of the instruction addressed to the controller electronic flight (23). Motorized paragliding propeller propulsion assembly according to claim 1 characterized in that the flight controller (23) is coupled to a GPS type location system to create automatic type piloting by automatically and asymmetrically varying the thrusts to follow a predefined GPS trajectory.