阅读说明：本技术 一种飞机起落架放下位置锁定装置 (Aircraft landing gear down position locking device ) 是由 李永洁 张剑剑 张立军 陶小将 于 2020-12-29 设计创作，主要内容包括：本发明公开了一种飞机起落架放下位置锁定装置,包括斜支柱,斜支柱的前端设置有倾斜段,斜支柱后端通过套筒固定在起落架支架上,斜支柱前端的倾斜段与起落架支臂固定连接；所述斜支柱的上表面上自倾斜段向斜支柱后端的方向开设有安装槽；安装槽中设置有摇臂、锁定机构以及弹簧复位机构。选用起落架承载结构件分别作为放下位置锁定机构的撑杆和锁钩功能件,成功地在极狭小的空间内布置出起落架放下位置锁定装置。放下位置锁定机构的锁定机构在放下位置不需承受较大的地面载荷,极大地减轻了机构的重量。复位弹簧具有双重功能在收起、放下过程中弹簧载荷有利于起落架运动；收放作动筒与摇臂连接点的选取,避开了放下位置锁定机构设定的机构死点。(The invention discloses a locking device for the down position of an aircraft landing gear, which comprises an inclined strut, wherein the front end of the inclined strut is provided with an inclined section, the rear end of the inclined strut is fixed on a landing gear bracket through a sleeve, and the inclined section at the front end of the inclined strut is fixedly connected with a landing gear support arm; an installation groove is formed in the upper surface of the inclined strut from the inclined section to the rear end of the inclined strut; the mounting groove is internally provided with a rocker arm, a locking mechanism and a spring reset mechanism. The landing gear bearing structural part is selected as a stay bar and a lock hook functional part of the landing gear down position locking mechanism respectively, and the landing gear down position locking device is successfully arranged in a very narrow space. The locking mechanism of the down position locking mechanism does not need to bear large ground load in the down position, and the weight of the mechanism is greatly reduced. The return spring has double functions, and the spring load is beneficial to the movement of the undercarriage in the processes of retraction and extension; the selection of the connection point of the retractable actuating cylinder and the rocker arm avoids the mechanism dead point set by the put-down position locking mechanism.)

1. An aircraft landing gear down position locking device, comprising a down stay (1), a rocker (5) and a bumper (7), wherein:

the front end of the oblique strut (1) is provided with an oblique section, the rear end of the oblique strut (1) is fixed on the undercarriage support, and the oblique section at the front end of the oblique strut (1) is fixedly connected with the undercarriage support arm; an installation groove is formed in the upper surface of the inclined strut (1) from the inclined section to the rear end of the inclined strut (1); a connecting shaft for connecting the landing gear support arm with the oblique strut (1) is positioned in the oblique section;

the rocker arm (5) is arranged in the mounting groove, the front end and the rear end of the rocker arm (5) are respectively provided with a pair of first fork lug (2) and second fork lug (6), and the first fork lug (2) and the second fork lug (6) are connected through an I-beam; a pair of connecting lugs (4) is arranged on the I-beam, and the connecting lugs (4) are connected with the retractable actuating cylinder of the undercarriage through a mounting rotating shaft; the side wall of the front end of the mounting groove is symmetrically provided with mounting holes, the pair of first fork lugs (2) are arranged in the mounting groove, and the mounting holes and the first fork lugs (2) are penetrated through by mounting rotating shafts, so that the rocker arm (5) can rotate through the first fork lugs (2); the pair of second fork lugs (6) are connected with the upper end of the buffer (7) through a mounting rotating shaft, the second fork lugs (6) can rotate relative to the upper end of the buffer (7), and a lower end lug (8) of the buffer (7) is mounted on the landing gear.

2. An aircraft landing gear down position locking device according to claim 1, wherein when the landing gear is in the down position, the axial midpoints of the pair of second prongs (6), the pair of first prongs (2) and the bumper (7) lower end tab (8) are connected in sequence to form a triangular structure, and the axial midpoint of the second prongs (6) is located below the line connecting the axial midpoints of the first prongs (2) and the bumper (7) lower end tab (8).

3. An aircraft landing gear down position locking device according to claim 2, characterised in that there is a twist angle of not less than 26 ° between the plane of symmetry of the pair of connection tabs (4) and the plane of symmetry of the first fork ear (2).

4. An aircraft landing gear down position locking device according to claim 1, characterised in that a pair of joints are provided on the sides of the connection tabs (4), through which a fixed shaft is provided, the ends of which are provided with spring hanging points (9); a spring joint (11) is arranged at the lower part of the front end of the oblique strut (1), and a return spring (10) is arranged between the spring joint (11) and the spring hanging point (9).

5. An aircraft landing gear down position locking device according to claim 1, characterized in that when the landing gear is in the down end stage, the axis midpoint of the first fork lug (2), the axis midpoint of the second fork lug (6) and the axis midpoint of the lug (8) at the lower end of the buffer (7) are connected into a straight line, the negative deflection strut lock structure is in a dead point position, the reset spring (10) is in a stretching state, and the load of the reset spring (10) is favorable for the landing gear to smoothly pass through the dead point and reach the down limit position; when the support rod is placed at the lower limit position, the reset spring (10) is in a stretching state, the tension of the reset spring (10) is favorable for maintaining the negative deflection of the support rod, and the locking structure of the negative deflection support rod is ensured to be locked at the placement position; in the landing gear stow position, the return spring (10) is also in tension, and the load of the return spring (10) facilitates the landing gear being held in the stow position.

6. An aircraft landing gear down position locking device according to claim 1, wherein a locking mechanism (3) is provided in the mounting slot, the lower surface of the locking mechanism (3) being secured to the inside wall of the mounting slot; the locking mechanism (3) is provided with a rotatable locking key, and a locking hook matched with the locking key is arranged on the rocker arm (5); when the undercarriage is in the down position, the locking key is attached to the surface of the locking hook, and the locking mechanism (3) limits the position of the rocker arm (5), so that the rocker arm (5) cannot rotate anticlockwise and the rocker arm (5) is locked.

7. An aircraft landing gear down position locking arrangement according to claim 1, characterised in that during retraction of the landing gear, the latch catch of the locking mechanism (3) is rotated by hydraulic actuation out of contact with the latch hook to unlock the rocker arm (5).

8. An aircraft landing gear down position locking device according to claim 1, wherein the cross-section of the oblique strut (1) in the axial direction is an "i" beam structure.

Technical Field

The invention relates to the field of aircraft structure design, in particular to a locking device for a landing gear down position of an aircraft.

Background

The landing gear down position locking device has the function of fixing the landing gear support at the down position, and the currently adopted down position locking mechanism is divided into an independent locking hook type and a supporting rod type.

The independent locking hook type locking principle is that a locking ring on a landing gear support moves into a locking hook U-shaped groove of a lower lock along the molded surface of a locking hook of the lower lock, and the locking ring is limited in the locking hook groove, so that the landing gear of the airplane is fixed at a put-down position. The locking principle of the brace rod is that a mechanical lock on a machine body or an undercarriage structure supports the foldable brace rod which moves to the down position, two component rod pieces of the foldable brace rod are designed with negative deflection, and the foldable brace rod is kept at the down position of the undercarriage under the action of the mechanical lock.

For the landing gear with limited arrangement space and large bearing load, no arrangement form of the down position locking mechanism with simple structure and small occupied space exists.

Disclosure of Invention

The invention aims to provide a locking device for the landing gear down position of an airplane, which aims to solve the problems that the existing locking mechanism cannot have a simple structure, is limited in installation space and bears large load.

In order to realize the task, the invention adopts the following technical scheme:

an aircraft landing gear down position locking device comprising a down stay, a rocker arm and a bumper, wherein:

the front end of the oblique strut is provided with an oblique section, the rear end of the oblique strut is fixed on the undercarriage support, and the oblique section at the front end of the oblique strut is fixedly connected with the undercarriage support arm; an installation groove is formed in the upper surface of the inclined strut from the inclined section to the rear end of the inclined strut; a connecting shaft for connecting the landing gear support arm with the oblique strut is positioned in the oblique section;

the rocker arm is arranged in the mounting groove, a pair of first fork lug and second fork lug are respectively arranged at the front end and the rear end of the rocker arm, and the first fork lug and the second fork lug are connected through an I-beam; a pair of connecting lugs are arranged on the I-beam and are connected with the retractable actuating cylinder of the undercarriage through a mounting rotating shaft; the side wall of the front end of the mounting groove is symmetrically provided with mounting holes, the pair of first fork lugs are arranged in the mounting groove, and the mounting holes and the first fork lugs are penetrated through by a mounting rotating shaft, so that the rocker arm can rotate through the first fork lugs; the pair of second fork lugs is connected with the upper end of the buffer through an installation rotating shaft, the second fork lugs can rotate relative to the upper end of the buffer, and the lower end lug of the buffer is installed on the undercarriage.

Further, when the undercarriage is located at the down position, the axial midpoint of the pair of second fork lugs, the axial midpoint of the pair of first fork lugs and the axial midpoint of the lug at the lower end of the buffer are sequentially connected to form a triangular structure, and the axial midpoint of the second fork lugs is located on the lower side of a connecting line of the axial midpoint of the first fork lugs and the axial midpoint of the lug at the lower end of the buffer.

Further, a torsion angle of not less than 26 ° exists between the symmetry plane of the pair of connection tabs and the symmetry plane of the first fork tab.

Furthermore, a pair of joints are arranged on the side surface of the connecting lug plate, a fixed shaft penetrates through the pair of joints, and spring hanging points are arranged at two ends of the fixed shaft; the lower part of the front end of the oblique strut is provided with a spring joint, and a return spring is arranged between the spring joint and a spring hanging point.

Further, when the undercarriage is at the tail end of the lower part, the axis midpoint of the first fork lug, the axis midpoint of the second fork lug and the axis midpoint of the lug at the lower end of the buffer are connected into a straight line, the negative deflection strut lock structure is at a dead point position, the return spring is in a stretching state at the moment, and the load of the return spring is favorable for the undercarriage to smoothly pass through the dead point and reach the limit position of the lower part; when the support rod is placed at the lower limit position, the reset spring is in a stretching state, the tension of the reset spring is favorable for maintaining the negative deflection of the support rod, and the locking structure of the support rod with the negative deflection is ensured to be locked at the placement position; in the landing gear stowed position, the return spring is also in tension and the return spring load facilitates the landing gear being held in the stowed position.

Furthermore, a locking mechanism is arranged in the mounting groove, and the lower surface of the locking mechanism is fixed on the inner side wall of the mounting groove; the locking mechanism is provided with a rotatable locking key, and the rocker arm is provided with a locking hook matched with the locking key; when the undercarriage is in the down position, the locking key is attached to the surface of the locking hook, and the locking mechanism limits the position of the rocker arm, so that the rocker arm cannot rotate anticlockwise, and the rocker arm is locked.

Furthermore, in the retraction process of the landing gear, the locking key of the locking mechanism is rotated through hydraulic driving, and is separated from the locking hook, so that the rocker arm is unlocked.

Furthermore, the cross section of the oblique strut along the axial direction is of an I-shaped beam structure.

Compared with the prior art, the invention has the following technical characteristics:

the invention selects the advantages of a brace rod type and an independent lock hook type, and creates an arrangement form of the locking mechanism at the putting down position. The undercarriage bearing structural part is selected as a support rod and a lock hook functional part of the undercarriage down position locking mechanism respectively, the mechanism is compact and ingenious, and the undercarriage down position locking device is successfully arranged in a very narrow space. The locking mechanism of the down position locking mechanism does not need to bear large ground load in the down position, and the weight of the mechanism is greatly reduced. The return spring has double functions, and the spring load is beneficial to the movement of the landing gear in the processes of retraction and extension; in the lowered and retracted extreme positions, the spring facilitates locking of the mechanism. The selection of the connection point of the retractable actuating cylinder and the rocker arm avoids the mechanism dead point set by the put-down position locking mechanism.

Drawings

FIG. 1 is a schematic view of the overall structure of the apparatus of the present invention;

FIG. 2 is an enlarged schematic view of the front end portion of the diagonal strut;

fig. 3 is a side view of the device (cross-section of the diagonal strut in the axial direction).

The reference numbers in the figures illustrate: the device comprises an inclined strut 1, a first fork lug 2, a locking mechanism 3, a connecting lug 4, a rocker arm 5, a second fork lug 6, a buffer 7, a lug at the lower end 8, a spring hanging point 9, a return spring 10 and a spring joint 11.

Detailed Description

As shown in fig. 1 to 3, the present invention provides an aircraft landing gear down position locking device comprising a down stay 1, a rocker arm 5 and a bumper 7, wherein:

the front end of the inclined strut 1 is provided with an inclined section, the rear end of the inclined strut 1 is fixed on the undercarriage support through a sleeve, and the inclined section at the front end of the inclined strut 1 is fixedly connected with the undercarriage support arm; an installation groove is formed in the upper surface of the inclined strut 1 from the inclined section to the rear end of the inclined strut 1; the landing gear support arm is located with the connecting axle that oblique support 1 is connected inside the slope section, and the design of slope section not only is convenient for pass through the connecting axle with the landing gear support arm and is connected, is favorable to the transmission of ground load to the fuselage moreover.

The rocker arm 5 is arranged in the mounting groove, a pair of first fork lug 2 and second fork lug 6 are respectively arranged at the front end and the rear end of the rocker arm 5, and the first fork lug 2 and the second fork lug 6 are connected through an I-beam; a pair of connecting lugs 4 are arranged on the I-beam, and the connecting lugs 4 are connected with a retractable actuating cylinder of the undercarriage through a mounting rotating shaft; wherein: a torsion angle of not less than 26 degrees is formed between the symmetrical plane of the pair of connecting lugs 4 and the symmetrical plane of the first fork lug 2; in addition, a deflection angle of 18 degrees is formed between the symmetrical plane of the pair of connecting lugs 4 and the plane formed by the axis of the first fork lug 6 and the axis of the second fork lug 2, so that the actuating cylinder can have a smaller installation angle, and the folding and unfolding efficiency is improved.

The side wall of the front end of the mounting groove is symmetrically provided with mounting holes, the pair of first fork lugs 2 are arranged in the mounting groove, and the mounting holes and the first fork lugs 2 are penetrated through by mounting rotating shafts, so that the rocker arm 5 can rotate through the first fork lugs 2; the pair of second lugs 6 are connected with the upper end of the buffer 7 through a mounting rotating shaft, the second lugs 6 can rotate relative to the upper end of the buffer 7, and the lower lug 8 of the buffer 7 is mounted on the landing gear.

It should be noted that when the landing gear is located in the down position, the axial midpoint a of the pair of second fork ears 6, the axial midpoint B of the pair of first fork ears 2, and the axial midpoint C of the lower end lug 8 of the bumper 7 are sequentially connected to form a triangular structure, and the axial midpoint of the second fork ears 6 is located on the lower side of the connecting line of the axial midpoint of the first fork ears 2 and the axial midpoint of the lower end lug 8 of the bumper 7. By adopting the structural design, the inclined strut 1, the rocker arm 5 and the buffer 7 form a negative deflection strut lock structure, when the undercarriage is in the down position, a certain distance L exists between the midpoint A and the connecting line BC, so that the negative deflection of the negative deflection strut lock is formed, and the undercarriage structural member is kept in the down position.

Optionally, the position of the pair of connecting lugs 4 on the rocker arm 5 is selected within a spatially allowable range, as far as possible from the axis of the first fork lug 2, so that when the frame is folded and dropped, the actuator load can effectively overcome the negative deflection of the strut assembly and the mechanism dead point.

In order to keep the negative deflection of the negative deflection brace rod lock, the scheme further designs two sets of double backup assemblies of a reset spring 10 and a locking mechanism 3, the functions of the two assemblies are independent, the reliability and the safety of the negative deflection brace rod lock are ensured, and the specific description is as follows:

a pair of joints are arranged on the side surface of the connecting lug plate 4, a fixed shaft penetrates through the pair of joints, and spring hanging points 9 are arranged at two ends of the fixed shaft; the lower part of the front end of the inclined strut 1 is provided with a spring joint 11, and a return spring 10 is arranged between the spring joint 11 and a spring hanging point 9.

The position of the spring hanging point 9 relative to the axis of the first fork 2 is chosen such that the return spring 10 can have a dual function:

when the undercarriage is at the tail end of the lowering, and the axis midpoint A of the first fork lug 2, the axis midpoint B of the second fork lug 6 and the axis midpoint C of the lug 8 at the lower end of the buffer 7 are connected into a straight line, the negative deflection strut lock structure is at a dead point position, at the moment, the return spring 10 is in a stretching state, and the load of the return spring 10 is beneficial for the undercarriage to smoothly pass through the dead point and reach the limit position of the lowering. When the support rod is placed at the lower limit position, the reset spring 10 is in a stretching state, the tension of the reset spring 10 is favorable for maintaining the negative deflection of the support rod, and the locking structure of the negative deflection support rod lock is ensured to be locked at the placement position; in the landing gear stowed position, the return spring 10 is also under tension and the load of the return spring 10 facilitates the maintenance of the landing gear in the stowed position.

In the scheme, the locking mechanism 3 is arranged in the mounting groove, and the lower surface of the locking mechanism 3 is fixed on the inner side wall of the mounting groove; the locking mechanism 3 is provided with a rotatable locking key, and the rocker arm 5 is provided with a locking hook matched with the locking key; when the undercarriage is in the down position, the locking key is automatically attached to the surface of the locking hook, and the locking mechanism 3 limits the position of the rocker arm 5, so that the rocker arm 5 cannot rotate anticlockwise, and the effect of locking the rocker arm 5 is achieved. In the retraction process of the landing gear, the latch key of the locking mechanism 3 is rotated by hydraulic drive, and is separated from contact with the latch hook, so that the rocker arm 5 is unlocked.

Optionally, the cross section of the inclined strut 1 along the axial direction is of an I-shaped beam structure, so that the space can be effectively saved, and the structure weight is also reduced by arranging a negative-deflection strut lock structure.

The above embodiments are only used for illustrating the technical solutions of the present application, and not for limiting the same; although the present application has been described in detail with reference to the foregoing embodiments, it should be understood by those of ordinary skill in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some technical features may be equivalently replaced; such modifications and substitutions do not substantially depart from the spirit and scope of the embodiments of the present application, and are intended to be included within the scope of the present application.