WO2021118391A1

WO2021118391A1 - Multicopter-type pilotless aircraft

Info

Publication number: WO2021118391A1
Application number: PCT/RU2019/000935
Authority: WO
Inventors: Наиль Рамилевич ЗИННУРОВ; Рафаэль Азатович ЯРМУШЕВ; Дмитрий Александрович АРСЕНТЬЕВ; Максим Сергеевич ЖИЛЬЦОВ
Original assignee: Общество С Ограниченной Ответственностью "Окб Авиарешения"
Priority date: 2019-12-12
Filing date: 2019-12-12
Publication date: 2021-06-17

Abstract

The invention relates to the field of aviation, and specifically to pilotless aircrafts of vertical take-off and landing. A multicopter-type aircraft comprises a plurality of rotors with propellers and a motor, an onboard computer and a fuel system. The fuel system comprises a fuel pump, two fuel tanks arranged symmetrically relative to the center of mass of the aircraft, fuel level sensors disposed in each tank, a fuel supply pipe and a fuel return pipe. Electromagnetic cutoff devices are disposed in the fuel return pipe before each fuel tank. The onboard computer can redistribute the weight of the fuel between the two fuel tanks by closing off the fuel return pipe of one tank containing a larger volume of fuel, determined by the fuel level sensors. One fuel tank is disposed in the nose of the aircraft and the second fuel tank is disposed in the tail of the aircraft in the direction of flight. The pitching balance of the aircraft in flight is improved.

Description

Unmanned aerial vehicle of multicopter type

The technical field to which the invention relates

The invention relates to the field of aviation, namely to vertical take-off and landing unmanned aerial vehicles.

State of the art

It is known from the prior art (RU 75634 U1, publ. 20.08.2008) an aircraft fuel system containing the main and additional outboard fuel tanks, installed in the main tank, an electric drive pump for powering the engines and a jet pump for pumping fuel into the main tank from additional outboard tanks along the line fuel transfer connected to the union of each additional external fuel tank. In this case, each additional suspended fuel tank is equipped with a device for visually determining the fuel consumption from this tank, which is made in the form of a pipe connected to the fitting, in which there are viewing windows and in the inner cavity of which there is a movable signal element, for example, a ball, vertically moved by dynamic pressure jets of fuel. The fuel system is equipped with a fuel return line.

It is also known from the prior art (RU 2134216 C1, publ. 20.06.2006) an aircraft fuel system containing front and rear additional tanks connected by transfer pipelines to a supply tank, a fuel supply pipeline to the engine, fuel transfer and supply pumps, command pressure pipelines, connected to the fuel transfer and supply pipelines, the fuel bypass pipeline. In this case, the fuel system is equipped with valves for pumping fuel installed in the transfer pipelines and having control cavities, respectively, from the front and rear additional tanks to the supply tank, two jet fuel level sensors connected to the command pressure pipeline, installed in the front and rear additional tanks, and a command switch with cavities control of the development of the front and rear additional tanks, over-plunger, sub-plunger and drain cavities. Moreover, the control cavity of each pumping valve is connected by a control line to the control cavity for the generation of the corresponding additional tank in the command switch, the supra-plunger and sub-plunger cavities of which are respectively communicated with the rear and front additional tanks through the outputs of their jet sensors, and the drain cavity of the command switch is connected to one of the tanks. From the prior art also (US 9868544 B2, publ. 05/07/2015) a fuel system is known, consisting of two tanks and a fuel supply line of each tank to the corresponding tank, the engine by means of pumps installed in each tank. The fuel system is equipped with a transfer pump and transfer line, allowing fuel to be supplied from one tank to the first or second engine.

Also from the prior art (CN 109808901 A, 05/28/2019) a fuel system is known that includes two auxiliary tanks installed in the wings; main tank installed in the fuselage; the first fuel line designed to return excess fuel; the second fuel line, designed to replenish the main tank from the auxiliary tanks; the third fuel line, designed to supply fuel to the engine. One pump is used to supply fuel from the auxiliary and main tanks. The second line is equipped with two valves to close / open the fuel supply from the auxiliary tanks.

The essence of the invention

The problem solved by the claimed invention is the creation of an unmanned aerial vehicle with a fuel system, which allows to prevent imbalance due to uneven production and filling of fuel tanks relative to each other, and, or to balance the aircraft in pitch in flight without a payload.

The technical result of the claimed invention is to prevent imbalance due to uneven production and filling of fuel tanks relative to each other, as well as to improve the balance of the unmanned aerial vehicle in pitch in flight.

The technical result of the claimed invention is achieved due to the fact that a multicopter-type unmanned aerial vehicle comprising a body, a plurality of rotors with propellers and an engine, an on-board computer and a fuel system, while the fuel system contains a fuel pump, two fuel tanks located symmetrically relative to the center aircraft masses, fuel level sensors located in each fuel tank, fuel supply line, return fuel line, electromagnetic locking devices located on the return fuel line in front of each said fuel tank, and the on-board computer is configured to redistribute the fuel weight between the two mentioned fuel tanks by blocking the return fuel line of one fuel tank containing a larger volume of fuel detected by the said fuel level sensors in each tank. In the particular case of the implementation of the claimed technical solution, one fuel tank is located on the nose of the aircraft in the direction of flight, and the second fuel tank is located in the tail of the aircraft in the direction of flight.

In the particular case of the implementation of the claimed technical solution, the on-board computer is configured to balance the aircraft in pitch in flight without a payload by distributing the volume of fuel between the said fuel tanks.

In the particular case of the implementation of the claimed technical solution, the engine is made in the form of an internal combustion engine.

Thanks to this arrangement of the system, the asymmetry of the distribution of the cargo weight is compensated by redistributing the weight of the fuel between the bow and tail fuel tanks, and, or balancing the aircraft in pitch in flight without a payload.

There is no need to install additional transfer pumps and an additional supply tank (see figure 3).

The system is lighter and more reliable due to the use of structurally simple solenoid valves (and similar electronic shut-off devices) and fuel level sensors.

Brief Description of Drawings

Details, features, and advantages of the present invention follow from the following description of embodiments of the claimed technical solution using the drawings, which show:

FIG. 1 - UAV fuel system with two tanks;

FIG. 2 is a schematic diagram of the fuel system;

In the figures, the following positions are designated by numbers: 1 - filler necks of fuel tanks with breathers built into the caps; 2 - fuel tanks; 3 - main line of fuel supply pipelines; 4 - tee fitting; 5 - coarse fuel filter; 6 - fuel pump; 7 - fine fuel filter; 8 - pressure regulator; 9 - fuel rail; 10 - return fuel line; 11 - electromagnetic locking devices; 12- fuel level sensor.

Terms and Definitions

For a better understanding of the present invention, below are some of the terms used in the present description of the invention. Unless otherwise specified, technical and scientific terms in this application have their standard meanings, generally accepted in scientific and technical literature.

In the present description and in the claims, the terms "includes", "including" and "includes", "having", "equipped", "containing" and their other grammatical forms are not intended to be construed in an exclusive sense, but, on the contrary, are used in a non-exclusive sense (ie, in the sense of "including"). Only expressions of the type “consisting of” should be considered as an exhaustive list.

In addition, the terms "first", "second", "third", etc. are used simply as conditional markers, without imposing any numerical or other restrictions on the enumerated objects.

The terms “connected”, “fixed”, “installed” mean functionally connected, and any number or combination of intermediate elements between the connected components can be used (including the absence of intermediate elements).

Detailed description of the invention

An unmanned aerial vehicle contains a body, a plurality of propeller-driven rotors, an engine, an on-board computer, and a fuel system.

The tanks of the aircraft fuel system are located equidistant relative to the geometric plane of symmetry of the UAV.

The fuel system of an unmanned aerial vehicle contains a fuel pump (6), two fuel tanks (2) located symmetrically relative to the center of mass of the aircraft, fuel level sensors (12) located in each fuel tank (2), a line (3) of fuel supply pipelines , a return fuel line (10), electromagnetic locking devices (11) located on the return fuel line in front of each said fuel tank.

The supply pipeline (3) is made from each fuel tank (2) by separate branches connected to a common pipeline by means of a tee fitting (4). A coarse filter (5) is installed on the fuel supply line (3) on the way to the fuel rail (9) of the engine, located in front of the fuel pump (6). Also, a fine filter (7) is installed on the fuel supply line (3) after the fuel pump (6) along the path of the fuel rail (9) of the engine. A pressure regulator (8) is installed on the fuel supply line (3) between said fine filter (7) and said fuel rail (9) of the engine.

To regulate the amount of fuel supplied to the system, a pressure regulator (8) is used from which the return (10) fuel line departs, through which excess fuel is returned to the fuel tanks (2). Fuel is pumped to the fuel rail (9) of the engine using a fuel pump (6) with a constant flow rate. The fuel pump (6) is designed as an electric pump.

To prevent atmospheric vacuum inside the fuel tanks (2), plugs with a built-in breather are provided at the filler (1) necks.

To prevent imbalance due to uneven filling of fuel tanks (2) relative to each other (displacement of the center of mass of the apparatus in pitch), electromagnetic locking devices (11) made in the form of valves are installed in both return fuel lines (10) of the fuel return in front of the fuel tanks ...

Electromagnetic locking devices (11) are connected by a digital channel with the UAV on-board computer and fuel level sensors (12). Electromagnetic locking devices (11) blocking the fuel supply to the tank, according to a signal from the on-board computer of the UAV when the difference in fuel mass is higher than the maximum permissible tolerance value for balancing in pitch.

When the on-board computer receives a signal from the fuel level sensors to reach an equal fuel level in both tanks, the first re-unlocks the previously locked return line. Data on the total fuel level, as well as data on the level difference between the front and rear tanks, are available to the on-board computer from the moment the UAV is launched, and therefore balancing to an equal volume of fuel in both tanks is performed even before the vehicle enters takeoff mode.

There is no need to install additional transfer pumps and an additional supply tank.

The system is lighter and more reliable due to the use of structurally simple solenoid valves (and similar electronic shut-off devices) and level sensors.

Although the present patent application relates to the invention defined in the claims appended below, one skilled in the art will readily understand that this patent application contains a basis for the formulation of other inventions, which may, for example, be claimed as the subject of the refined claims of the present application or as the subject of the claims. inventions in a divisional and / or continuing application. Such an object can be characterized by any feature or combination of features described herein.

Claims

Claim

1. An unmanned aerial vehicle of a multicopter type, containing, a body, a plurality of rotors with propellers and an engine, an on-board computer and a fuel system, while the fuel system contains a fuel pump, two fuel tanks located symmetrically relative to the center of mass of the aircraft, fuel level sensors, located in each fuel tank, the fuel supply line, the return fuel line, electromagnetic locking devices located on the return fuel line in front of each said fuel tank, and the on-board computer is configured to redistribute the fuel weight between the two said fuel tanks by blocking the return fuel line of one a fuel tank containing a larger volume of fuel detected by said fuel level sensors in each tank.

2. The aircraft according to claim 1, characterized in that one fuel tank is located on the nose of the aircraft in the direction of flight, and the second fuel tank is located in the tail of the aircraft in the direction of flight.

3. An aircraft according to claim 1, characterized in that the on-board computer is configured to balance the aircraft in pitch in flight without a payload by distributing the volume of fuel between said fuel tanks.

4. An aircraft according to claim 1, wherein the engine is in the form of an internal combustion engine.