EA041745B1 - LIGHT MULTI-PURPOSE AIRCRAFT CHASSIS AND MAIN GEAR SUPPORT - Google Patents

Description

The invention relates to the field of aviation, namely to the landing gear of aircraft and the main landing gear, and can be used in the construction of manned and unmanned light aircraft.

An aircraft chassis is known (patent for the invention RU 2649111, published on 03/29/2018), containing the right and left struts with wheels fixed to them, the struts are pivotally fixed in brackets connected to the aircraft body with the help of trunnions, and through one of the trunnions, by means of splines, are connected to a longitudinal torsion bar having a lever at the other end, by means of which the torsion bar is connected to a pneumatic cylinder, which acts as an adjustable stop during torsion bar operation, in addition, each rack has a damper.

The disadvantage of the described analogue is the excessive complexity of the design, due to which the weight of the structure is increased and the complexity of manufacturing is increased.

The closest technical solution chosen as a prototype for the claimed invention is a non-retractable aircraft landing gear (application for invention RU 97107081, published on 04/10/1999), containing the front and main supports, shock absorbers, racks with wheels, characterized in that each the main support strut is made with a cross-section in the form of a streamlined profile and is mounted on an axle located inside the aircraft fuselage, on which a lever is fixed, connecting the strut with a shock absorber, and the lever and shock absorber are placed inside the aircraft fuselage.

The disadvantage of the prototype is the possibility of its use only in the designs of take-off and landing devices with a nose support, the permeability of which is much lower than that of devices with a tail support. The axis on which the main support strut is installed is located inside the fuselage, which complicates the maintenance of the strut during operation.

The objective of the invention is to eliminate the above disadvantages.

The technical result, to which the invention is directed, is to simplify the kinematic diagram of the landing gear, reduce the weight of their design and simplify the manufacturing technology, making it possible to use the main landing gear both in landing gear devices with nose and tail landing gear, increasing reliability and simplifying the maintenance of the structure. chassis.

To achieve the specified technical result, a landing gear for a light multi-purpose aircraft (LMS) and the main landing gear are proposed.

Landing gear for light multi-purpose aircraft is non-retractable and consists of two main bearings and one tail bearing. Each of the struts of the main supports has a welded structure and consists of a tubular lever, at the end of which a wheel with a brake is fixed, in the upper part the tubular lever has an axis on which it can rotate during shock absorption, in addition, a shock absorber lever is installed on the axis, which is included inside the fuselage , pivotally connected to the shock absorber, which is also placed inside the fuselage and the other end is pivotally connected to the fuselage, while the axis is located outside the fuselage frame and enclosed in a removable fairing. The tail support consists of a semi-lever suspension strut with a centering device and a non-braking wheel.

The main landing gear consists of a tubular lever, at the end of which a wheel is fixed, in the upper part of the tubular lever has an axis on which the lever can be rotated during depreciation, in addition, a shock absorber lever is installed on the axis, which enters the inside of the fuselage, is pivotally connected to the shock absorber, which is also placed inside the fuselage and the other end is pivotally connected to the fuselage, while the axis is located outside the fuselage frame and enclosed in a removable fairing.

The shock absorbers are located at an angle to the transverse axis of the aircraft, towards each other, while the angle of inclination is not more than 30°.

The essence of the invention is illustrated by drawings.

In FIG. 1 shows the general layout of the chassis.

In FIG. 2, 3 shows a diagram of the main landing gear.

In FIG. 4 shows the lever hinge assembly.

In FIG. 5 shows the wheel mount.

In FIG. 6 shows the installation unit of the signaling device of the compressed position of the chassis.

In FIG. 7 shows the tail landing gear.

The following designations are used in the figures:

- main landing gear;

- tail landing gear;

- tubular levers;

- beam;

- fuselage;

- boar;

- shock absorber;

- wheels of the main supports;

- tail wheel;

, 11- frames;

- 1 041745

- traverse;

- back bracket;

- steps;

- removable fairing axis of the lever;

- shields;

- signaling device of the compressed position of the chassis;

- suspension strut tail support;

- fuselage bracket;

- tail support link;

- towing carrier connection point;

- tail wheel stopper;

- tubular lever fairing;

- fist.

The design of the landing gear is made according to three basic schemes with a tail wheel. The landing gear is made non-retractable, consists of two main bearings 1 and one tail bearing 2.

The main landing gear supports 1 are made according to a lever scheme with racks in the form of tubular levers 3 fixed on a transverse beam 4 in the lower part of the fuselage 5. Each rack has a welded structure, including a tubular lever 3, in the upper part of which there is a boar (shock absorber lever) 6 for connection with the shock absorber 7, and in the lower part - a fist 24, on which the wheel axle 8 is fixed. The lever 3 is fixed on the traverse 12 of the lever axis, the trunnions (not shown in the figures) of which are pivotally mounted on the brackets 13, mounted on the brackets 19 of the frames fuselage. Traverse 12 with trunnions at the ends form an axis on which the lever 3 can rotate during damping, while the axis is enclosed in a removable fairing 15. Shock absorbers 7 are located at an angle to the transverse axis of the aircraft, towards each other, inside the transverse beam 4, resting at one end on wild boar 6, and the other on the crossbar of the beam 4, closing the shock absorbers of the right and left main supports, while the angle of inclination is not more than 30 °.

Lever 3 is pivotally mounted on frames 10 and 11, transferring the load from wheel 8 to shock absorber 7. Shock absorber 7 is located in the fuselage, which significantly reduces aerodynamic drag compared to other non-retractable landing gear schemes. The lever hinge assembly on the frame 10 receives and transmits loads to the fuselage along all X, Y, Z axes, the lever hinge assembly on the frame 11 perceives and transmits loads to the fuselage only along the Y and Z axes. The lever axis included in the rear bracket 13 can slide along the axis of rotation. The rear bracket 13, in turn, is included in the fuselage bracket 19 on the frame 11 with the ability to move when mounting the axis of the rear bracket 11 along the Y and Z axes.

Steps 14 are provided on lever 3 to enter the cab through the front doors. To reduce aerodynamic drag, fairing 23 is installed on lever 3.

To prevent collisions of objects thrown by the wheels of the landing gear with the structural elements of the aircraft, shields 16 are installed on each landing gear behind the wheel. An indicator of the compressed position of the landing gear 17 is installed on the axis of the right support.

The tail support 2 consists of a shock-absorbing strut 18 of a semi-lever type and a non-braking wheel 9. Its fastening is carried out on the frame using the fuselage bracket 19 and link 20. The tail support is freely oriented during taxiing and can be rotated through 360°. The centering device (not shown in the figures) in the spring strut 18 ensures that the wheel 9 is installed in the flight line, from the position turned to the left or right at an angle of ±15°, when the axial load is removed from the wheel. On the cylinder of the shock absorber 18, a connection point for the towing carrier 21 is organized. On the shock absorber 18, a stopper 22 is installed to automatically fix the wheel 9 in the flight line when the hydraulic pressure is turned off, its release from the hydraulic pressure generated manually from the cockpit, and also mechanically controlled manually when disconnected hydraulic pressure during ground handling. The tail wheel 9, like the main wheels, is equipped with a shield (not shown in the figures).

All landing gear legs are equipped with mechanical rough landing indicators (not shown in the figures).

The devices work as follows.

When an aircraft lands, a vertically acting force acts on the wheel, as a result of which the rack lever moves around the longitudinal axis on the brackets: the boar in the root part of the lever acts on the shock absorber, which, compressing, absorbs energy, while simultaneously performing the damping function.

The main landing gear of the LMS can be used both in the takeoff and landing gear with a nose gear and in the takeoff and landing gear with a tail gear. This allows the claimed design to be used on a larger number of aircraft types and improves the maneuverability of the take-off and landing device as a whole when using the tail support. Each rack is the main

- 2 041745 LMS support in cross section is made in the form of a round pipe that takes all the loads, this makes it possible to simplify the manufacturing technology and reduce the cost of the product, while maintaining aerodynamic and weight characteristics. The axis on which the LMS strut is installed is located outside the fuselage frame, in a removable fairing, which makes it possible to simplify maintenance of the strut during operation. The shock absorber lever connecting the strut to the shock absorber of the LMS is part of the strut, which reduces the number of movable joints and the number of parts of the chassis strut. This, in turn, increases reliability and simplifies maintenance of the rack during operation.

The analysis of patent and scientific and technical literature did not reveal technical solutions with a similar set of essential features, which allows us to conclude that the novelty of the claimed invention meets the criterion.

The claimed essential features, predetermining the receipt of the specified technical result, do not explicitly follow from the prior art, which allows us to conclude that the claimed invention complies with the condition of patentability and inventive step.

Claims (7)

1. Landing gear for a light multi-purpose aircraft, made non-retractable, consisting of two main legs and one tail leg, characterized in that each of the legs of the main legs has a welded structure and consists of a tubular lever, at the end of which a wheel with a brake is fixed, in the upper part the tubular lever has an axis, while the lever is configured to rotate on this axis during depreciation, in addition, the shock absorber lever is installed on the axis, which enters the inside of the fuselage, is pivotally connected to the shock absorber, which is also placed inside the fuselage and the other end is pivotally connected to the fuselage, while the axis is located outside the fuselage frame and enclosed in a removable fairing. 2. Chassis for a light multi-purpose aircraft according to claim 1, characterized in that the axis is formed by a traverse with trunnions at the ends. 3. Chassis for a light multi-purpose aircraft according to claim 1, characterized in that the tail support consists of a semi-lever suspension strut with a centering device and a non-braking wheel. 4. Chassis for a light multi-purpose aircraft according to claim 1, characterized in that the shock absorbers are located at an angle to the transverse axis of the aircraft, towards each other, while the angle of inclination is not more than 30°. 5. The main landing gear for a light multi-purpose aircraft, consisting of a tubular lever, at the end of which a wheel is fixed, characterized in that the tubular lever has an axis in the upper part, while the lever is rotatable on this axis during depreciation, in addition, on The axis is equipped with a shock absorber lever, which enters the inside of the fuselage, is pivotally connected to the shock absorber, which is also placed inside the fuselage and the other end is pivotally connected to the fuselage, while the axis is located outside the fuselage frame and enclosed in a removable fairing. 6. The main landing gear for a light multi-purpose aircraft according to claim 5, characterized in that the axle is formed by a traverse with trunnions at the ends. 7. The main landing gear for a light multi-purpose aircraft according to claim 5, characterized in that the shock absorbers are located at an angle to the transverse axis of the aircraft, towards each other, while the angle of inclination is not more than 30°.