CN117326053A - Helicopter tail wheel locking system and tail wheel operating method - Google Patents

Abstract

The invention discloses a helicopter tail wheel locking system and a tail wheel operating method, wherein the system comprises the following steps: the device comprises a tail wheel lock, a tail buffer device, an electromechanical management unit, an avionic display unit, a prompting lamp box and a switch; the electromechanical management unit is electrically connected with the switch and a tail wheel lock arranged on the tail buffer device respectively; the helicopter tail wheel locking system sends a tail wheel lock control signal to the electromechanical management unit through pilot switch operation, and the electromechanical management unit transmits the received control signal to the tail wheel lock to drive an output shaft of an electric mechanism in the tail wheel lock to execute corresponding movement, so that a mechanical lock and a lock pin which are in linkage in the tail wheel lock are driven to generate linkage movement, and electric locking, electric unlocking or electric locking after manual unlocking of the tail wheel lock is realized.

Description

Helicopter tail wheel locking system and tail wheel operating method

Technical Field

The invention relates to the technical field of helicopter landing gears, in particular to a helicopter tail wheel locking system and a tail wheel operating method.

Background

Helicopters typically employ passive turning techniques to achieve ground turning functions. In order to realize the ground turning function, the tail landing gear of the helicopter has a free orientation function, can freely rotate left and right around a rotating shaft of the tail landing gear, and turns along with the ground in the ground movement process. The free directional function may cause the helicopter to enter dangerous conditions such as tail sideslip, shimmy, etc. under ramp landing, running, etc. Therefore, in the above situation, it is necessary to lock the tail wheel of the tail gear in the neutral position, preventing the tail gear from rotating. The tail wheel needs to be unlocked before the turning function is used during taxiing.

Based on the above description of the use of the tail landing gear of a helicopter, in order to put the tail landing gear in a steering lock condition in the event of a landing on a slope, running on a ski, etc., the pilot needs to be able to maneuver the tail wheel lock during parking, taxiing, in the air, etc. However, the taxiing phase tail gear cannot be held in a neutral position for a long period of time, and the difficulty of locking the tail wheel is greatest at this phase; the problem of difficult locking of the tail wheel (low locking rate) occurs to different degrees in the development process of various helicopters. In addition, the phenomenon of tail wheel unlocking jamming can occur due to the existence of lateral force when the tail wheel is unlocked.

Disclosure of Invention

The purpose of the invention is that: in order to solve the problems, the embodiment of the invention provides a helicopter tail wheel locking system and a tail wheel operating method, which are used for solving the problems that in the design of locking and unlocking a helicopter tail wheel, the difficulty of locking the tail wheel in a sliding stage is greatest, and the phenomenon of tail wheel unlocking jamming occurs due to lateral force during unlocking.

The technical scheme of the invention is as follows: the embodiment of the invention provides a helicopter tail wheel locking system, which comprises: the tail wheel lock 3, the tail buffer device 4, the electromechanical management unit 6 and the switch 2;

wherein the electromechanical management unit 6 is electrically connected with the switch 2 and the tail wheel lock 3 arranged on the tail buffer device 4 respectively;

the helicopter tail wheel locking system is used for sending tail wheel lock control signals to the electromechanical management unit 6 through the operation of a pilot on the switch 2, and the electromechanical management unit 6 transmits the received control signals to the tail wheel lock 3 to drive an output shaft of an electric mechanism in the tail wheel lock 3 to execute corresponding motions, so that the mechanical lock and the lock pin which are in linkage in the tail wheel lock 3 are driven to generate linkage motions, and electric locking, electric unlocking or electric locking after manual unlocking of the tail wheel lock 3 is realized.

Optionally, in the helicopter tail wheel locking system as described above, further comprising: an avionics display unit 1 and a prompting lamp box 5 which are respectively connected with an electromechanical management unit 6;

the helicopter tail wheel locking system is also used for feeding back the current state of the helicopter tail wheel locking system to the prompting lamp box 5 and the avionic display unit 1 through the electromechanical management unit 6 by the tail wheel lock 3, wherein the current state comprises a tail wheel unlocking state, a tail wheel locking state and a tail wheel clamping state.

Optionally, in the helicopter tail wheel locking system as described above, the tail buffer device 4 has a fixed structure and a rotating structure, an upper lock hole is arranged on the fixed structure, and a lower lock hole which is matched and locked is arranged on the rotating structure; the tail-wheel lock 3 comprises: an electric mechanism 310, a mechanical lock 320 connected to the electric mechanism 310, and a lock pin 328 connected to the mechanical lock 320, the lock pin 328 being inserted into the fixed upper lock hole;

the electric mechanism 310 is electrically connected to the electromechanical management unit 6, and performs a movement of a corresponding position according to a control signal sent by the electromechanical management unit 6, and drives the mechanical lock 320 and the lock pin 328 to move, so as to control the lock pin 328 to be inserted into or pulled out from the lower lock hole.

Alternatively, in a helicopter tail wheel locking system as described above,

the tail buffer device 4 comprises: nut 41, center rod 42, outer cylinder 43, rotary cylinder 44, piston 45 and piston rod 46;

the outer cylinder 43 is fixed on the machine body structure, the rotary cylinder 44 is embedded in the outer cylinder 43 part and can rotate around the outer cylinder 43, the inner end of the rotary cylinder is in abutting contact with the same side end of the outer cylinder 43, the central rod 42 passes through the same side ends of the rotary cylinder 44 and the outer cylinder 43, the inner end of the rotary cylinder 44 is abutted in the outer cylinder 43 through an annular boss in the middle of the central rod 42, and the extending end of the central rod 42 is fixed through the nut 41 so as to fix the central rod 42 with the outer cylinder 43; the other end of the rotary cylinder 44 is provided with a piston rod 45, a piston 45 in the piston rod 46 divides a cavity between the rotary cylinder 44 and the piston rod 45 into an oil cavity and an air cavity, and the bottom end of the piston rod 46 is connected with a machine wheel 47;

the open end of the outer cylinder 43 is provided with an annular boss, the middle part of the cylinder wall of the rotary cylinder 44 is provided with a middle boss, and the middle boss is abutted against the bottom of the annular boss; an upper lock hole is formed in the annular boss, and a lower lock hole matched and locked is formed in the middle boss; the upper lock hole is positioned at the fixed position of the tail starting buffer device, and the lower lock hole rotates along with the rotating shaft of the tail starting buffer device.

Alternatively, in a helicopter tail wheel locking system as described above,

when the tail wheel lock 3 locks the tail wheel, the lock pin of the tail wheel lock 3 is inserted into the lower lock hole from the upper lock hole under the control of the electric mechanism 310, so that the rotation of the rotary cylinder 44 is limited, namely the rotation of the tail landing gear is limited; when the tail wheel is unlocked, the lock pin of the tail wheel lock 3 is retracted into the upper lock hole from the lower lock hole under the control of the electric mechanism 310, so that the rotary cylinder 44 can rotate freely, i.e. the tail landing gear can rotate freely.

Alternatively, in a helicopter tail wheel locking system as described above,

in the structure of the tail-wheel lock 3, the mechanical lock 320 includes: the lock comprises a lock shell 321, a linkage pull rod 322, a mechanical lock spring 323, a lower pull rod 324, an upper pull rod 325, an upper lock spring 326 and a steel ball 327; wherein, a mechanical lock spring 323 is arranged in the lock shell 321, the top end of the mechanical lock spring 323 is propped against the inner wall of the top end of the shell 321, the mechanical lock spring 323 is connected with a lower pull rod 324, and the lower pull rod 324 is connected with a lock pin 328; an upper lock is arranged in the platform at the top end of the lower pull rod 324;

the motor output shaft 311 of the electric mechanism 310 goes deep into the lock shell 321, the bottom end of the motor output shaft 311 is connected with the upper pull rod 325, and the lower end of one side of the upper pull rod 325 is provided with a downward convex upper lock unlocking boss; a linkage pull rod 322 is arranged between the upper pull rod 325 and the lower pull rod 324; an upper lock disposed within the top platform of lower tie rod 324 is used to lock locking pin 328 in the unlocked position.

Alternatively, in a helicopter tail wheel locking system as described above,

the upper lock comprises an upper lock spring 326 and a steel ball 327 which are arranged in a platform at the top end of the lower pull rod 324, and when the mechanical lock 320 is in the unlocking position, the steel ball 327 is embedded into a groove in the middle of the lock shell 321 so as to limit the movement of the lower pull rod 324.

Optionally, in the helicopter tail wheel locking system as described above, the tail wheel lock 3 further includes: a manual unlocking mechanism 350 for manually unlocking the tail wheel;

wherein, manual unlocking mechanism 350 includes: a knock pin 351, a mounting bracket 352, and a handle 353; the manual unlocking mechanism 350 is installed on the rotary cylinder 44 through a mounting bracket 352, the handle 353 is hinged with the mounting bracket 352 to rotate around a hinge point of the mounting bracket 352, the jacking pin 351 is located at the bottom of the locking pin 328, one end of the jacking pin is in contact with the locking pin 328 after jacking, the locking pin 328 is jacked into the upper locking hole to realize manual unlocking, and the other end of the jacking pin 328 is connected with a kidney-shaped hole on the handle 353.

Alternatively, in a helicopter tail wheel locking system as described above,

the tail-wheel lock 3 further comprises: an unlocking micro switch 340 provided at an unlocking position of the lock pin 328, and a locking micro switch 330 disposed at a locking position of the lock pin 328;

the unlocking micro switch 340 and the locking micro switch 330 are respectively connected to the indicator light box 5 for indicating the locking state and unlocking state of the tail wheel lock 3 through the indicator light box 5.

Alternatively, in a helicopter tail wheel locking system as described above,

the tail wheel lock 3 has a lock pin jamming indication function, and the electric mechanism 310 judges whether the lock pin 328 is jammed or not through internal current in the unlocking process.

Alternatively, in a helicopter tail wheel locking system as described above,

the manner in which the electric mechanism 310 determines whether the lock pin 328 is stuck by the internal current is as follows: during the electric unlocking process, when the current in the electric mechanism 310 increases, and when the current increases to a preset threshold value and lasts for 3 seconds, the electric mechanism 310 outputs a clamping stagnation signal to the avionic display unit and the indicator light box 5 through the electromechanical management unit 6 so as to prompt the pilot to execute unlocking after adjusting the centering positions of the upper and lower lock holes in the tail buffer device 4.

Alternatively, in a helicopter tail wheel locking system as described above,

the tail wheel lock 3 is provided with a 2-stage travel, and the electric mechanism 310 has 3 positions, namely: an unlocking position, a locking position and an unlocking upper locking position.

Alternatively, in a helicopter tail wheel locking system as described above,

the switch 2 is set as a 3-gear switch and is provided with a locking gear, an initial gear and an unlocking gear, and the initial gear can be automatically restored after each electric locking or electric unlocking.

The embodiment of the invention also provides a helicopter tail wheel operating method, which is implemented by adopting the helicopter tail wheel locking system and comprises the following steps:

electric locking tail wheel, electric unlocking tail wheel, manual locking tail wheel, and electric locking tail wheel after manual unlocking.

Alternatively, in the helicopter tail wheel manipulation method as described above,

the helicopter tail wheel locking system performs the mode of electrically locking the tail wheel by: after the electric mechanism 310 receives the locking signal sent by the push switch 2, the motor output shaft 311 is driven to move downwards to drive the upper pull rod 325 to move downwards, the steel ball 327 is pressed into the lower pull rod 324 through the upper lock unlocking boss, the lower pull rod 324 is unlocked, the lock pin 328 is driven to move downwards under the action of the mechanical lock spring 323 after the lower pull rod 324 is unlocked, and the lock pin 328 is inserted into the lower lock hole from the upper lock hole, so that electric locking is completed.

Alternatively, in the helicopter tail wheel manipulation method as described above,

the helicopter tail wheel locking system performs the mode of electrically unlocking the tail wheel as follows: after the electric mechanism 310 receives an unlocking signal sent by the push switch 2, the output shaft 311 of the driving motor moves upwards to drive the upper pull rod 325, the linkage pull rod 322 and the lower pull rod 324 to move upwards, so that the lock pin 328 is driven to be pulled out of the lower lock hole, and the upper lock spring 326 in the lower pull rod 324 drives the steel ball 327 to enter into a groove on the inner wall of the lock shell 321, so that the lock pin 328 is locked at the unlocking position, and electric unlocking is realized.

Alternatively, in the helicopter tail wheel manipulation method as described above,

the helicopter tail wheel locking system performs manual tail wheel locking by the following steps: the lock pin 328 is lifted up to the unlocking position by the manual unlocking mechanism, and in the unlocking position of the lock pin 328, the upper lock spring 326 in the lower pull rod 324 drives the steel ball 327 to enter the groove in the inner wall of the lock shell 321, so that the lock 328 is locked at the unlocking position, and manual unlocking is realized.

Alternatively, in the helicopter tail wheel manipulation method as described above,

the helicopter tail wheel locking system performs electric locking of the tail wheel after manual unlocking in the following way: the upper pull rod 325 and the linkage pull rod 322 in the electric mechanism 310 and the mechanical lock 320 of the manual unlocking rear tail wheel lock 3 are positioned at the tail wheel lock locking position; after the tail wheel lock 3 receives the locking signal, the motor output shaft 311 moves downwards under the drive of the electric mechanism 310 to drive the upper pull rod 325 to move downwards, and the upper lock unlocking boss of the upper pull rod 325 presses the steel ball 327 into the top end platform of the lower pull rod 324 to unlock the lower pull rod 324; the lower pull rod 324 moves downward under the action of the mechanical lock spring 323 to realize the locking function.

Alternatively, in the helicopter tail wheel manipulation method as described above,

the electric mechanism 310 automatically returns to the locking position after reaching the unlocking and locking position.

The invention has the beneficial effects that: the embodiment of the invention provides a helicopter tail wheel locking system and a tail wheel operating method, which can realize electric locking and electric unlocking of a tail wheel by adopting a motor driving mode, and are provided with a manual driving mechanism, so that the manual locking of the tail wheel can be realized, the electric mechanism of a tail wheel lock is continuously powered by a power supply, and corresponding actions can be executed after receiving an instruction. The technical scheme of the invention has the following beneficial effects:

the invention adopts the electric drive mode, the tail wheel lock can be arranged at a position far away from a pilot or a hydraulic source, and energy and signals are transmitted through wires, so that the invention has the advantages of light weight and high reliability.

2, the invention adopts a mode of driving the lock pin by a spring to realize the function of locking the tail wheel in the ground sliding stage, and the mode can realize 100 percent locking rate.

And 3, the problem of unlocking clamping stagnation is solved by adopting a conical lock pin mode, and 100% unlocking is realized.

4, the invention can realize automatic switching of manual and automatic modes; in order to realize the function, a three-gear resettable switch and a 2-stage travel tail wheel lock are adopted.

The lock pin of the invention has a shear groove design, and can protect the peripheral structure under the condition of misoperation.

And 6, the invention accurately indicates the tail wheel locking state through three signals of 'tail wheel locking', 'tail wheel unlocking' and 'tail wheel locking clamping stagnation', thereby being convenient for pilot to operate.

And 7, the overload protection function is realized by arranging the shearing groove on the lock pin of the tail wheel lock. When the side load exceeds the design value, the lock pin is sheared at the shearing groove, so that the peripheral structure can be protected.

Drawings

The accompanying drawings are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate and do not limit the invention.

FIG. 1 is a schematic diagram of a system architecture for a helicopter tail wheel locking system provided by an embodiment of the invention;

FIG. 2 is a schematic diagram of a tail buffer device in a helicopter tail wheel locking system according to an embodiment of the invention;

FIG. 3 is a schematic view of the locking pin and the upper and lower locking holes of the tail wheel lock in the tail buffer device provided in the embodiment shown in FIG. 2;

fig. 4 is a schematic diagram of the principle of locking the tail wheel in the tail buffer device provided in the embodiment shown in fig. 3, in which fig. 4 a is an unlocked state and fig. b is a locked state;

FIG. 5 is a schematic view of the structure of a lock pin in a tailwheel lock according to an embodiment of the present invention;

fig. 6 is a schematic structural diagram of a tail wheel lock in a helicopter tail wheel locking system provided by an embodiment of the invention; and the schematic diagram of the principle of the tail wheel lock of fig. 6 performing electric locking;

fig. 7 is a schematic diagram of the principle of the tail wheel lock provided in the embodiment shown in fig. 6 to perform electric unlocking;

FIG. 8 is a schematic diagram of the tail-wheel lock according to the embodiment of FIG. 6 for performing manual unlocking;

fig. 9 is a schematic gear diagram of a switch in an embodiment of the invention.

Detailed Description

The following description of the embodiments of the present invention will be made clearly and completely with reference to the accompanying drawings, in which it is apparent that the embodiments described are only some embodiments of the present invention, but not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.

It has been described in the background section above that, based on the use of the above-described helicopter tail landing gear, pilots need to be able to maneuver the tail wheel lock during parking, taxiing, in the air, etc. However, helicopter tail wheels lock and unlock the problem in two ways: on the one hand, the tail landing gear cannot be kept in a neutral position for a long time during the taxiing phase, so that the difficulty of locking the tail wheel is greatest at this phase; on the other hand, the side force exists during unlocking, so that the phenomenon of tail wheel unlocking jamming occurs. I.e. locking and unlocking the tail wheel during the taxiing phase is a design difficulty of the tail wheel locking system.

At present, the mode of increasing locking force and unlocking force can improve the probability of successful locking and unlocking to a certain extent, but can not fundamentally solve the problem of difficult locking and unlocking of the tail wheel.

The ground crew also needs to unlock the tail wheel when towing the helicopter to turn. A "manual switch tail lock to manual mode" approach is typically employed. The tail wheel is unlocked manually in manual mode. In manual mode, the pilot cannot operate the tail lock due to the disengagement of the lock pin from the ram. If the ground crew pulls and finishes the helicopter and does not switch the tail wheel lock to an automatic state, certain potential safety hazards exist. In addition, if the tail gear lock is not unlocked before towing the turn, the tail landing gear may be damaged by being subjected to excessive loads.

The helicopter adopting the front three-point landing gear layout can operate the front wheels to lock and unlock in a manual or hydraulic mode. The rear three-point helicopter is relatively costly to use in a manual or hydraulic operation mode because the tail wheel lock is far away from the pilot. Therefore, the electric scheme is more suitable to be adopted.

In view of the above problems, the embodiment of the present invention provides a helicopter tail wheel locking system, and the tail wheel locking system provided by the embodiment of the present invention is required to solve the following problems:

1. the tail wheel can be locked and unlocked in the sliding stage;

2. the automatic switching between the manual mode and the automatic mode can be realized, so that the pilot can normally use the ground crew after unlocking the tail wheel;

3. the tail landing gear can be prevented from being damaged due to misoperation during traction;

4. the electric scheme is convenient to be arranged at a position far away from the pilot.

The following specific embodiments may be combined with each other, and some embodiments may not be repeated for the same or similar concepts or processes.

Example 1

Fig. 1 is a schematic diagram of a system architecture of a helicopter tail wheel locking system according to an embodiment of the invention. The helicopter tail wheel locking system provided by the embodiment of the invention comprises the following components: the device comprises a tail wheel lock 3, a tail buffer device 4, an electromechanical management unit 6, an avionic display unit 1, a prompting lamp box 5 and a switch 2.

In the structure of the helicopter tail wheel locking system shown in fig. 1, an electromechanical management unit 6 is electrically connected with an avionics display unit 1, a switch 2, a warning light box 5, and a tail wheel lock 3 mounted on a tail buffer device 4, respectively.

According to the helicopter tail wheel locking system, a tail wheel lock control signal (comprising a locking signal and an unlocking signal) is sent to the electromechanical management unit 6 through the operation of a pilot on the switch 2, the electromechanical management unit 6 transmits the received control signal to the tail wheel lock 3 to drive an output shaft of an electric mechanism in the tail wheel lock 3 to execute corresponding movement, so that a mechanical lock and a lock pin which are in linkage in the tail wheel lock 3 are driven to generate linkage, and electric locking, electric unlocking or electric locking after manual unlocking of the tail wheel lock 3 is realized.

According to the helicopter tail wheel locking system provided by the embodiment of the invention, the tail wheel lock 3 can feed back the current state of the tail wheel lock to the prompting lamp box 5 and the avionic display unit 1 through the electromechanical management unit 6, wherein the current state comprises a tail wheel unlocking state, a tail wheel locking state and a tail wheel clamping state.

In particular, after the electromechanical management unit 6 receives the locking and unlocking status signals sent by the tail wheel lock 3, the status signals are transmitted to the indicator light box 5 and the avionics display unit 1. After receiving the lock state signal, the "tail wheel lock" on the indicator lamp box 5 indicates that the lamp is on, and the avionic display unit 1 displays the "tail wheel lock". After receiving the unlocking state signal, the tail wheel unlocking prompt lamp on the prompt lamp box 5 is lightened, and the avionic display unit 1 displays the tail wheel unlocking. After the tail wheel lock 3 sends out a clamping stagnation state signal, the electromechanical management unit 6 sends out a tail wheel lock clamping stagnation signal to the prompting lamp box 5, and the avionic display unit 1 displays the tail wheel lock clamping stagnation.

The tail wheel locking system provided by the embodiment of the invention can realize the automatic switching function of the electric mode and the manual mode. After being energized, the tail wheel can be operated to lock or unlock by the switch 2. The manual unlocking function can be realized in the power-on and power-off state. The electric locking can be realized after the manual unlocking, and the manual switching to the electric mode is not needed in the process.

In this embodiment, the tail buffer device 4 has a fixed structure and a rotating structure, wherein the fixed structure is provided with an upper lock hole, and the rotating structure is provided with a lower lock hole which is matched and locked; the tail-wheel lock 3 comprises: an electric mechanism 310, a mechanical lock 320 connected to the electric mechanism 310, and a lock pin 328 connected to the mechanical lock 320, the lock pin 328 being inserted into the fixed upper lock hole;

the electric mechanism 310 is electrically connected to the electromechanical management unit 6, and performs a movement of a corresponding position according to a control signal sent by the electromechanical management unit 6, and drives the mechanical lock 320 and the lock pin 328 to move, so as to control the lock pin 328 to be inserted into or pulled out from the lower lock hole.

The following describes the implementation of each of the above functions in detail by means of the structural form of the tail buffer device 4 and the tail lock 3.

Example 2

Fig. 2 is a schematic structural diagram of a tail buffer device in a helicopter tail wheel locking system according to an embodiment of the invention. The tail-starting buffer device provided by the embodiment of the invention comprises: nut 41, center rod 42, outer cylinder 43, rotary cylinder 44, piston 45 and piston rod 46; the tail stock buffer is mounted on a wheel 47 by means of a piston rod 46.

In the structure of the tail-up buffer device 4 shown in fig. 2, an outer cylinder 43 is fixed on a machine body structure, a rotary cylinder 44 is mounted inside the outer cylinder 43 by embedding and can rotate around the outer cylinder 43, the inner end of the rotary cylinder is in abutting contact with the same side end of the outer cylinder 43, a center rod 42 passes through the same side ends of the rotary cylinder 44 and the outer cylinder 43, the inner end of the rotary cylinder 44 is abutted into the outer cylinder 43 through an annular boss in the middle of the center rod 42, and the extending end of the center rod 42 is fixed through a nut 41 so as to fix the center rod 42 and the outer cylinder 43; the other end of the rotary cylinder 44 is fitted into a piston rod 45, a piston 45 in a piston rod 46 divides a cavity between the rotary cylinder 44 and the piston rod 45 into an oil cavity and an air cavity, and the bottom end of the piston rod 46 is connected with a wheel 47.

On the tail-lifting buffer device 4, an annular boss is arranged at the opening end of the outer cylinder 43, a middle boss is arranged in the middle of the cylinder wall of the rotary cylinder 44, and the middle boss is abutted against the bottom of the annular boss; an upper lock hole is formed in the annular boss, and a matched lower lock hole is formed in the middle boss. The upper lock hole is positioned at the fixed position of the tail starting buffer device, and the lower lock hole can rotate along with the rotating shaft of the tail starting buffer device. As shown in fig. 3, a schematic diagram of the lock pin and the upper and lower lock holes of the tail wheel lock in the tail buffer device according to the embodiment shown in fig. 2 is provided. Fig. 4 is a schematic diagram of the principle of locking the tail wheel in the tail buffer device provided in the embodiment shown in fig. 3, where fig. 4 a is an unlocked state and fig. b is a locked state. In the unlocked state, the rotary cylinder 44 and the piston rod 46 in the tail buffer device 4 can rotate with the landing gear.

In this embodiment, when the tail wheel is locked, the lock pin of the tail wheel lock 3 is inserted into the lower lock hole from the upper lock hole, so that the rotation of the rotary cylinder 44, that is, the rotation of the tail landing gear is restricted. When unlocking the tail wheel, the lock pin of the tail wheel lock 3 is retracted into the upper lock hole from the lower lock hole, and the rotary cylinder 44 can rotate freely at this time, so that the tail landing gear can rotate freely, as shown in fig. 2 and 3.

Example 3

The main reasons for the difficulty in locking the tail wheel of the helicopter in the sliding stage are as follows: when the tail wheel is unlocked, the rotation of the rotary drum 44 drives the middle boss and the lower lock hole to rotate, so that the upper lock hole and the lower lock hole fixed on the tail starting buffer device 4 cannot always maintain an aligned state. In order to be able to lock in a short centering time, the invention employs a spring-driven locking pin 328 to lock, with a reasonable choice of spring, allowing the locking pin 328 to be inserted into the lower locking hole in a very short time.

Fig. 5 is a schematic structural diagram of a lock pin in a tailwheel lock according to an embodiment of the present invention. In order to solve the problem of unlocking jamming, the invention adopts a conical lock pin structure, and the lock pin moves upwards during unlocking, so that the lock pin can be instantaneously separated from the lower lock hole, thereby avoiding the phenomenon of unlocking jamming.

Further, the latch structure is shown in fig. 5. An annular shear groove is provided in the middle of the lock pin 328. The annular shear groove is positioned at the contact surface of the upper lock hole and the lower lock hole during locking. When misoperation occurs (the tail wheel is rotated in an unlocked state), the lock pin can be sheared at the shearing groove after the side load is increased to a certain degree, so that the effect of protecting the peripheral structure is achieved.

Fig. 6 is a schematic structural diagram of a tail wheel lock in a helicopter tail wheel locking system according to an embodiment of the invention. In a specific implementation of the embodiment of the present invention, the tail wheel lock 3 includes: an electric mechanism 310, a mechanical lock 320 coupled to the electric mechanism 310, and a locking pin 328 coupled to the mechanical lock 320.

As shown in fig. 6 for the structure of the mechanical lock 320, the mechanical lock 320 includes: the lock comprises a lock shell 321, a linkage pull rod 322, a mechanical lock spring 323, a lower pull rod 324, an upper pull rod 325, an upper lock spring 326 and a steel ball 327; wherein, a mechanical lock spring 323 is arranged in the lock shell 321, the top end of the mechanical lock spring 323 is propped against the inner wall of the top end of the shell 321, the mechanical lock spring 323 is connected with a lower pull rod 324, and the lower pull rod 324 is connected with a lock pin 328; an upper lock is installed in the top platform of the lower pull rod 324, the upper lock comprises an upper lock spring 326 and a steel ball 327 which are arranged in the top platform of the lower pull rod 324, and when the mechanical lock 320 is in an unlocking position, the steel ball 327 is embedded into a groove in the middle of the lock shell 321 so as to limit the movement of the lower pull rod 324.

The motor output shaft 311 of the electric mechanism 310 goes deep into the lock shell 321, the bottom end of the motor output shaft 311 is connected with the upper pull rod 325, and the lower end of one side of the upper pull rod 325 is provided with a downward convex upper lock unlocking boss. A linkage pull rod 322 is arranged between the upper pull rod 325 and the lower pull rod 324; an upper lock disposed within the top platform of lower tie rod 324 is used to lock locking pin 328 in the unlocked position. The uplock shown in fig. 6 is of a steel ball lock configuration, consisting of an uplock spring 326 and a steel ball 327.

In one implementation of the embodiment of the present invention, the tail wheel lock further includes: a manual unlocking mechanism; the manual unlocking mechanism 350 includes: a top pin 351, a mounting bracket 352, and a handle 353. Wherein the manual unlocking mechanism 350 is mounted on the rotary cylinder 44 by a mounting bracket 352. The handle 353 is hinged to the mounting bracket 352 and is rotatable about a hinge point of the mounting bracket 352. The jacking pin 351 is located at the bottom of the locking pin 328, and one end of the jacking pin is in contact with the locking pin 328 after jacking, so that the locking pin 328 is jacked into the upper locking hole to realize manual unlocking. The other end of the knock pin 328 is connected to a kidney-shaped hole in the handle 353.

Example 4

This embodiment provides an implementation for performing tail-wheel operations using a helicopter tail-wheel locking system. As shown in fig. 6, the present invention employs a 2-stage travel tail-wheel lock 3, and the electric mechanism 310 in fig. 6 has 3 positions, respectively: an unlocking position, a locking position and an unlocking upper locking position. The tail wheel lock 3 in the embodiment of the invention is adopted to execute the following electric locking tail wheel, electric unlocking tail wheel, manual locking tail wheel, manual unlocking tail wheel and electric locking tail wheel after manual unlocking.

(1) The mode of the electric locking tail wheel is as follows: the pilot presses the switch 2 to send locking signals to the electromechanical management unit 6 and forwards the locking signals to the electric mechanism 310 of the tail wheel lock 3, after the electric mechanism 310 receives the locking signals, the motor output shaft 311 moves downwards to drive the upper pull rod 325 to move downwards, an upper lock unlocking boss on the upper pull rod 325 can press the steel ball 327 into the lower pull rod 324 to unlock the lower pull rod 324, namely after the lower pull rod 324 is unlocked through the upper lock, the lower pull rod 324 drives the lock pin 328 to move downwards under the action of the mechanical lock spring 323, and the lock pin 328 is inserted into the lower lock hole from the upper lock hole, so that the electric locking function of the tail wheel is realized. The electric mechanism 310 automatically returns to the locking position after reaching the unlocking upper locking position. As shown in fig. 6, a schematic diagram of the principle of the tail wheel lock to perform electric locking is shown.

(2) The mode of electronic unblock tailwheel is: the pilot presses the switch 2 to send an unlocking signal to the electromechanical management unit 6 and forwards the unlocking signal to the electric mechanism 310 of the tail wheel lock 3, after the electric mechanism 310 receives the unlocking signal, the electric mechanism 310 drives the motor output shaft 311 to move upwards, and the motor output shaft 311 drives the upper pull rod 325, the linkage pull rod 322 and the lower pull rod 324 to move upwards, so that the lock pin 328 is driven to move from the locking position to the unlocking position (namely, the lock pin 328 is pulled out from the lower lock hole). The upper pull rod 325 is in the unlocking position of the lock pin 328 (corresponding to the unlocking position of the motor output shaft 311 in the electric mechanism 310), and the upper lock spring 326 in the lower pull rod 324 drives the steel ball 327 to enter the groove in the inner wall of the lock shell 321, so that the lock pin 328 is locked in the unlocking position, and electric unlocking is realized. Fig. 7 is a schematic diagram of the principle of the tail wheel lock provided in the embodiment shown in fig. 6 to perform electric unlocking.

(3) The mode of manual unblock tailwheel is: upon manual unlocking, the lock pin 328 is lifted up to the unlocked position by the manual unlocking mechanism. Because the lower pull rod 324 and the lock pin 328 follow, in the unlocking position of the lock pin 328, the upper lock spring 326 in the lower pull rod 324 drives the steel ball 327 to enter the groove on the inner wall of the lock shell 321, so that the lock 328 is locked in the unlocking position, and manual unlocking is realized. Fig. 8 is a schematic diagram of the principle of the tail wheel lock provided in the embodiment shown in fig. 6 to perform manual unlocking.

(4) The mode of the electric locking tail wheel after manual unlocking is as follows: the upper pull rod 325 and the linkage pull rod 322 in the electric mechanism 310 and the mechanical lock 320 of the manual unlocking rear wheel lock 3 are still in the rear wheel lock locking position. After the tail wheel lock 3 receives the locking signal, the motor output shaft 311 moves downwards under the driving of the electric mechanism 310 to drive the upper pull rod 325 to move downwards, and the upper lock unlocking boss in the upper pull rod 325 presses the steel ball 327 into the top platform of the lower pull rod 324 to unlock the lower pull rod 324. The lower pull rod 324 moves downward under the action of the mechanical lock spring 323 to realize the locking function. The electric mechanism 310 automatically returns to the locking position after reaching the unlocking upper locking position. As shown in fig. 6.

Example 5

In the tail wheel lock 3 provided by the embodiment of the invention, the micro switches are respectively arranged at the unlocking position and the locking position of the lock pin 328, namely the unlocking micro switch 340 and the locking micro switch 330, and the two micro switches are respectively connected to the prompting lamp box 5, so that the locking state and the unlocking state of the tail wheel lock 3 can be indicated. The lock signal is output when the tail-wheel lock 3 is in the locked state (the lock pin 328 is in the locked position), and the unlock signal is output when the tail-wheel lock 3 is in the unlocked state. The tail wheel lock 3 has a lock pin jamming indication function, and a jamming phenomenon occurs in the unlocking process, such as that of the lock pin 328.

In a particular implementation, the locking pin 328 is stuck as judged by the current inside the electric mechanism 310. In the electric unlocking process, if the lock pin 328 is jammed, the motor output shaft 311 needs to pull the pull-up rod 325 with a larger output force, at this time, the current in the electric mechanism 310 will be greatly increased, and after the current increases to a certain value (the current value corresponding to the maximum output power of the electric mechanism 310) for 3 seconds, the electric mechanism 310 will provide a jammed signal to the outside. To prompt the pilot to perform unlocking after adjusting the centering positions of the upper and lower lock holes in the tail jack 4.

It should be noted that, after the tail wheel lock 3 in the embodiment of the present invention is adopted to electrically unlock, the motor output shaft 311 is located at the unlocking position, and the upper pull rod 325 and the linkage pull rod 322 are driven to corresponding positions by the output shaft 311.

However, after manual unlocking, the lower link 324 is pushed up to the upper lock position and locked by the upper lock, but since the motor is not active, the output shaft 311 is still in the locked position, and the upper link 325 and the linkage link 322 are also in the locked position; therefore, it is difficult to electrically lock the vehicle after manual unlocking. To solve the above-described problem, the 3-speed switch 2 is adopted in the embodiment of the present invention, and a switch that locks and unlocks only two speeds cannot be adopted. The two-gear switch is in a locking gear after the electric locking is operated. After the tail wheel lock 3 is unlocked manually (at this time, the switch 2 is still in the locked gear position), the electric locking operation still needs to be performed again, and the two-gear switch cannot realize the function.

The locking signal and the unlocking signal are provided by a micro switch. The conventional 2-speed switch cannot realize the electric locking operation after manual unlocking. In the embodiment of the invention, the 3-gear switch with the automatic reset function is used. Fig. 9 is a schematic diagram of a gear of a switch according to an embodiment of the present invention. The intermediate gear is an initial gear, and the intermediate gear can automatically recover to the initial gear after each electric locking or electric unlocking. Any manipulation can be executed according to the requirement, so that the electric locking function after manual unlocking is realized.

According to the helicopter tail wheel locking system and the tail wheel operating method provided by the embodiment of the invention, the electric locking and the electric unlocking of the tail wheel can be realized by adopting a motor driving mode, the manual locking of the tail wheel can be realized by adopting a manual driving mechanism, the electric mechanism of the tail wheel lock is continuously powered by a power supply, and corresponding actions can be executed after receiving the instruction. The technical scheme of the invention has the following beneficial effects:

the invention adopts the electric drive mode, the tail wheel lock can be arranged at a position far away from a pilot or a hydraulic source, and energy and signals are transmitted through wires, so that the invention has the advantages of light weight and high reliability.

2, the invention adopts a mode of driving the lock pin by a spring to realize the function of locking the tail wheel in the ground sliding stage, and the mode can realize 100 percent locking rate.

And 3, the problem of unlocking clamping stagnation is solved by adopting a conical lock pin mode, and 100% unlocking is realized.

4, the invention can realize automatic switching of manual and automatic modes; in order to realize the function, a three-gear resettable switch and a 2-stage travel tail wheel lock are adopted.

The lock pin of the invention has a shear groove design, and can protect the peripheral structure under the condition of misoperation.

And 6, the invention accurately indicates the tail wheel locking state through three signals of 'tail wheel locking', 'tail wheel unlocking' and 'tail wheel locking clamping stagnation', thereby being convenient for pilot to operate.

And 7, the overload protection function is realized by arranging the shearing groove on the lock pin of the tail wheel lock. When the side load exceeds the design value, the lock pin is sheared at the shearing groove, so that the peripheral structure can be protected.

Although the embodiments of the present invention are described above, the present invention is not limited to the embodiments which are used for understanding the present invention. Any person skilled in the art can make any modification and variation in form and detail without departing from the spirit and scope of the present disclosure, but the scope of the present disclosure is to be determined by the appended claims.

Claims (19)

1. A helicopter tail wheel locking system comprising: the tail wheel lock 3, the tail buffer device 4, the electromechanical management unit 6 and the switch 2;

wherein the electromechanical management unit 6 is electrically connected with the switch 2 and the tail wheel lock 3 arranged on the tail buffer device 4 respectively;

the helicopter tail wheel locking system is used for sending tail wheel lock control signals to the electromechanical management unit 6 through the operation of a pilot on the switch 2, and the electromechanical management unit 6 transmits the received control signals to the tail wheel lock 3 to drive an output shaft of an electric mechanism in the tail wheel lock 3 to execute corresponding motions, so that the mechanical lock and the lock pin which are in linkage in the tail wheel lock 3 are driven to generate linkage motions, and electric locking, electric unlocking or electric locking after manual unlocking of the tail wheel lock 3 is realized.

2. The helicopter tail wheel locking system of claim 1, further comprising: an avionics display unit 1 and a prompting lamp box 5 which are respectively connected with an electromechanical management unit 6;

the helicopter tail wheel locking system is also used for feeding back the current state of the helicopter tail wheel locking system to the prompting lamp box 5 and the avionic display unit 1 through the electromechanical management unit 6 by the tail wheel lock 3, wherein the current state comprises a tail wheel unlocking state, a tail wheel locking state and a tail wheel clamping state.

3. The helicopter tail wheel locking system according to claim 2, wherein the tail-up buffer device 4 has a fixed structure and a rotating structure, wherein an upper lock hole is arranged on the fixed structure, and a lower lock hole which is matched and locked is arranged on the rotating structure; the tail-wheel lock 3 comprises: an electric mechanism 310, a mechanical lock 320 connected to the electric mechanism 310, and a lock pin 328 connected to the mechanical lock 320, the lock pin 328 being inserted into the fixed upper lock hole;

the electric mechanism 310 is electrically connected to the electromechanical management unit 6, and performs a movement of a corresponding position according to a control signal sent by the electromechanical management unit 6, and drives the mechanical lock 320 and the lock pin 328 to move, so as to control the lock pin 328 to be inserted into or pulled out from the lower lock hole.

4. A helicopter tail wheel locking system as claimed in claim 3 wherein,

the tail buffer device 4 comprises: nut 41, center rod 42, outer cylinder 43, rotary cylinder 44, piston 45 and piston rod 46;

the outer cylinder 43 is fixed on the machine body structure, the rotary cylinder 44 is embedded in the outer cylinder 43 part and can rotate around the outer cylinder 43, the inner end of the rotary cylinder is in abutting contact with the same side end of the outer cylinder 43, the central rod 42 passes through the same side ends of the rotary cylinder 44 and the outer cylinder 43, the inner end of the rotary cylinder 44 is abutted in the outer cylinder 43 through an annular boss in the middle of the central rod 42, and the extending end of the central rod 42 is fixed through the nut 41 so as to fix the central rod 42 with the outer cylinder 43; the other end of the rotary cylinder 44 is provided with a piston rod 45, a piston 45 in the piston rod 46 divides a cavity between the rotary cylinder 44 and the piston rod 45 into an oil cavity and an air cavity, and the bottom end of the piston rod 46 is connected with a machine wheel 47;

the open end of the outer cylinder 43 is provided with an annular boss, the middle part of the cylinder wall of the rotary cylinder 44 is provided with a middle boss, and the middle boss is abutted against the bottom of the annular boss; an upper lock hole is formed in the annular boss, and a lower lock hole matched and locked is formed in the middle boss; the upper lock hole is positioned at the fixed position of the tail starting buffer device, and the lower lock hole rotates along with the rotating shaft of the tail starting buffer device.

5. The helicopter tail wheel locking system of claim 4 wherein,

when the tail wheel lock 3 locks the tail wheel, the lock pin of the tail wheel lock 3 is inserted into the lower lock hole from the upper lock hole under the control of the electric mechanism 310, so that the rotation of the rotary cylinder 44 is limited, namely the rotation of the tail landing gear is limited; when the tail wheel is unlocked, the lock pin of the tail wheel lock 3 is retracted into the upper lock hole from the lower lock hole under the control of the electric mechanism 310, so that the rotary cylinder 44 can rotate freely, i.e. the tail landing gear can rotate freely.

6. The helicopter tail wheel locking system of claim 5 wherein,

in the structure of the tail-wheel lock 3, the mechanical lock 320 includes: the lock comprises a lock shell 321, a linkage pull rod 322, a mechanical lock spring 323, a lower pull rod 324, an upper pull rod 325, an upper lock spring 326 and a steel ball 327; wherein, a mechanical lock spring 323 is arranged in the lock shell 321, the top end of the mechanical lock spring 323 is propped against the inner wall of the top end of the shell 321, the mechanical lock spring 323 is connected with a lower pull rod 324, and the lower pull rod 324 is connected with a lock pin 328; an upper lock is arranged in the platform at the top end of the lower pull rod 324;

the motor output shaft 311 of the electric mechanism 310 goes deep into the lock shell 321, the bottom end of the motor output shaft 311 is connected with the upper pull rod 325, and the lower end of one side of the upper pull rod 325 is provided with a downward convex upper lock unlocking boss; a linkage pull rod 322 is arranged between the upper pull rod 325 and the lower pull rod 324; an upper lock disposed within the top platform of lower tie rod 324 is used to lock locking pin 328 in the unlocked position.

7. The helicopter tail wheel locking system of claim 6 wherein,

the upper lock comprises an upper lock spring 326 and a steel ball 327 which are arranged in a platform at the top end of the lower pull rod 324, and when the mechanical lock 320 is in the unlocking position, the steel ball 327 is embedded into a groove in the middle of the lock shell 321 so as to limit the movement of the lower pull rod 324.

8. The helicopter tail wheel locking system of claim 7 wherein the tail wheel lock 3 further comprises: a manual unlocking mechanism 350 for manually unlocking the tail wheel;

wherein, manual unlocking mechanism 350 includes: a knock pin 351, a mounting bracket 352, and a handle 353; the manual unlocking mechanism 350 is installed on the rotary cylinder 44 through a mounting bracket 352, the handle 353 is hinged with the mounting bracket 352 to rotate around a hinge point of the mounting bracket 352, the jacking pin 351 is located at the bottom of the locking pin 328, one end of the jacking pin is in contact with the locking pin 328 after jacking, the locking pin 328 is jacked into the upper locking hole to realize manual unlocking, and the other end of the jacking pin 328 is connected with a kidney-shaped hole on the handle 353.

9. The helicopter tail wheel locking system of claim 8 wherein,

the tail-wheel lock 3 further comprises: an unlocking micro switch 340 provided at an unlocking position of the lock pin 328, and a locking micro switch 330 disposed at a locking position of the lock pin 328;

the unlocking micro switch 340 and the locking micro switch 330 are respectively connected to the indicator light box 5 for indicating the locking state and unlocking state of the tail wheel lock 3 through the indicator light box 5.

10. The helicopter tail wheel locking system of claim 9 wherein,

the tail wheel lock 3 has a lock pin jamming indication function, and the electric mechanism 310 judges whether the lock pin 328 is jammed or not through internal current in the unlocking process.

11. The helicopter tail wheel locking system of claim 10 wherein,

the manner in which the electric mechanism 310 determines whether the lock pin 328 is stuck by the internal current is as follows: during the electric unlocking process, when the current in the electric mechanism 310 increases, and when the current increases to a preset threshold value and lasts for 3 seconds, the electric mechanism 310 outputs a clamping stagnation signal to the avionic display unit and the indicator light box 5 through the electromechanical management unit 6 so as to prompt the pilot to execute unlocking after adjusting the centering positions of the upper and lower lock holes in the tail buffer device 4.

12. The helicopter tail wheel locking system of claim 8 wherein,

the tail wheel lock 3 is provided with a 2-stage travel, and the electric mechanism 310 has 3 positions, namely: an unlocking position, a locking position and an unlocking upper locking position.

13. The helicopter tail wheel locking system of claim 12 wherein,

the switch 2 is set as a 3-gear switch and is provided with a locking gear, an initial gear and an unlocking gear, and the initial gear can be automatically restored after each electric locking or electric unlocking.

14. A method of helicopter tail wheel manipulation, wherein the method of helicopter tail wheel manipulation is performed using the helicopter tail wheel locking system of claim 13, comprising:

electric locking tail wheel, electric unlocking tail wheel, manual locking tail wheel, and electric locking tail wheel after manual unlocking.

15. The helicopter tail wheel manipulation method of claim 14 wherein,

the helicopter tail wheel locking system performs the mode of electrically locking the tail wheel by: after the electric mechanism 310 receives the locking signal sent by the push switch 2, the motor output shaft 311 is driven to move downwards to drive the upper pull rod 325 to move downwards, the steel ball 327 is pressed into the lower pull rod 324 through the upper lock unlocking boss, the lower pull rod 324 is unlocked, the lock pin 328 is driven to move downwards under the action of the mechanical lock spring 323 after the lower pull rod 324 is unlocked, and the lock pin 328 is inserted into the lower lock hole from the upper lock hole, so that electric locking is completed.

16. The helicopter tail wheel manipulation method of claim 14 wherein,

the helicopter tail wheel locking system performs the mode of electrically unlocking the tail wheel as follows: after the electric mechanism 310 receives an unlocking signal sent by the push switch 2, the output shaft 311 of the driving motor moves upwards to drive the upper pull rod 325, the linkage pull rod 322 and the lower pull rod 324 to move upwards, so that the lock pin 328 is driven to be pulled out of the lower lock hole, and the upper lock spring 326 in the lower pull rod 324 drives the steel ball 327 to enter into a groove on the inner wall of the lock shell 321, so that the lock pin 328 is locked at the unlocking position, and electric unlocking is realized.

17. The helicopter tail wheel manipulation method of claim 14 wherein,

the helicopter tail wheel locking system performs manual tail wheel locking by the following steps: the lock pin 328 is lifted up to the unlocking position by the manual unlocking mechanism, and in the unlocking position of the lock pin 328, the upper lock spring 326 in the lower pull rod 324 drives the steel ball 327 to enter the groove in the inner wall of the lock shell 321, so that the lock 328 is locked at the unlocking position, and manual unlocking is realized.

18. The helicopter tail wheel manipulation method of claim 14 wherein,

the helicopter tail wheel locking system performs electric locking of the tail wheel after manual unlocking in the following way: the upper pull rod 325 and the linkage pull rod 322 in the electric mechanism 310 and the mechanical lock 320 of the manual unlocking rear tail wheel lock 3 are positioned at the tail wheel lock locking position; after the tail wheel lock 3 receives the locking signal, the motor output shaft 311 moves downwards under the drive of the electric mechanism 310 to drive the upper pull rod 325 to move downwards, and the upper lock unlocking boss of the upper pull rod 325 presses the steel ball 327 into the top end platform of the lower pull rod 324 to unlock the lower pull rod 324; the lower pull rod 324 moves downward under the action of the mechanical lock spring 323 to realize the locking function.

19. The helicopter tail wheel manipulation method of claim 15 or 18 wherein,

the electric mechanism 310 automatically returns to the locking position after reaching the unlocking and locking position.