Helicopter blade folding supporting rod fixing device

Abstract

The utility model belongs to the technical field of helicopter connecting structures, and particularly relates to a helicopter blade folding supporting rod fixing device. Comprising a cross rod, a bushing, a circumferential limiting pin, an axial limiting pin and a spherical joint, the lining is mounted on a tail beam frame of the aircraft body, and the cross rod penetrates through the lining to be connected with the aircraft body structure; the circumferential limiting pin is mounted on the cross rod, and after the cross rod is mounted in place, the cross rod is aligned and inserted into a machine body quick-release pin hole, so that circumferential locking of the cross rod is realized; the axial limiting pin is installed on the cross rod in an interference fit mode, the length of the axial limiting pin is larger than the outer diameter of the cross rod, and the axial limiting pin is used for axially fixing the cross rod. And the spherical joint is fixed on the cross rod through a bolt and is used for being connected with the lower joint of the folding support rod.

Description

Technical Field

[0001] This utility model belongs to the technical field of helicopter connection structure, and specifically relates to a helicopter rotor blade folding strut fixing device. Background Technology

[0002] When helicopters perform rapid airlift missions, they need to be loaded into transport aircraft for rapid transport to the mission area, and then quickly restored to combat readiness. Due to the limited width of the transport aircraft cabin, the helicopter's main rotor blades need to be folded. The manual folding method involves removing one of the two blade pins, allowing the blade to rotate around the other pin, thus achieving folding. Due to the transport aircraft's overload, the folded rotor blades experience significant wobbling during transport, causing them to collide with the transport aircraft's inner walls, seriously affecting flight safety. Invention CN109533276B describes a rotary rotor blade clamping device that clamps the folded rotor blades, but it lacks a fixation mechanism to the fuselage. To prevent rotor blade wobbling during transport, it is necessary to secure the manually folded rotor blades. Utility Model Content

[0003] Purpose of this utility model: This application aims to design a helicopter rotor blade folding strut fixing device to compensate for the positional error caused by manual folding of the rotor blades, reduce rotor blade swaying during transportation, and improve loading and transportation flight safety.

[0004] Technical solution

[0005] A helicopter rotor blade folding strut fixing device includes: a crossbar, a bushing, a circumferential limiting pin, an axial limiting pin, and a ball joint;

[0006] The bushing is installed on the tail beam frame of the fuselage, and the crossbar passes through the bushing and is connected to the fuselage structure.

[0007] The circumferential limit pin is installed on the crossbar. After the crossbar is installed in place, it is aligned with the quick-release pin hole of the machine body and inserted to achieve circumferential locking of the crossbar.

[0008] The axial limiting pin is installed on the crossbar with an interference fit. Its length is greater than the outer diameter of the crossbar and it is used to fix the crossbar axially.

[0009] The ball joint is bolted to the crossbar and is used to connect to the lower joint of the folding strut.

[0010] Furthermore, the inner wall of the bushing is symmetrically provided with two L-shaped grooves.

[0011] Furthermore, the circumferential limit pin includes a limit pin body, a limit pin sleeve, a handle, a handle sleeve, and a spring;

[0012] The limit pin sleeve is fixed to the crossbar by rivets;

[0013] One end of the limit pin is provided with a shoulder to prevent it from coming out of the limit pin sleeve, and the other end passes through the handle sleeve and is connected to the handle by threads.

[0014] One end of the handle sleeve is fixed to one side of the limit pin sleeve by a threaded connection, and the other end is provided with a U-shaped groove. By lifting and rotating the handle, the handle can be fixed in two positions, and the circumferential limit pin can be fixed and released at the same time.

[0015] The spring is sleeved on the limiting pin, with one end limited by the shoulder of the limiting pin and the other end limited by the handle sleeve. When the circumferential limiting pin is unlocked, the shoulder of the limiting pin drives the spring to compress, and the handle moves out of the U-shaped groove and rotates to fix it. When the circumferential limiting pin is locked, the handle is rotated into the U-shaped groove, and the compressed spring automatically presses the limiting pin into the mounting hole of the machine body, thereby realizing the automatic fixing of the circumferential limiting pin.

[0016] Furthermore, the length of the axial limiting pin is greater than the outer diameter of the crossbar, and the exposed length on both sides after installation is the same as the depth of the L-shaped groove in the bushing. When the crossbar is installed, it drives the axial limiting pin to move linearly along the L-shaped groove and then rotates to the position, thereby fixing the crossbar along its axial direction.

[0017] Furthermore, the ball head radius of the ball joint is the same as the inner spherical surface of the lower joint of the folding strut, and the diameter of the ball head arm is the same as the U-shaped opening size of the lower joint of the folding strut.

[0018] Furthermore, the device also includes: a plug;

[0019] The cap is installed at the end of the crossbar to prevent foreign objects from entering during outdoor storage.

[0020] In summary, the beneficial effects of this utility model are as follows:

[0021] A helicopter rotor blade folding strut fixing device simultaneously meets the requirements of rapid installation, overload bearing, and compensation for rotor blade folding position errors, thereby improving loading, transportation, and flight safety. Attached Figure Description

[0022] Figure 1 A schematic diagram of a helicopter rotor blade folding strut fixing device;

[0023] Figure 2 This is a schematic diagram of a circumferential limit pin.

[0024] Figure 3 This is a schematic diagram of the bushing.

[0025] Figure 4 A schematic diagram showing the angular relationship of the limit pin design.

[0026] Figure 5 This is a schematic diagram of a ball joint connection. Detailed Implementation

[0027] To enable those skilled in the art to better understand the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present application, and not all embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative effort should fall within the scope of protection of the present application.

[0028] In this application, the terms "upper," "lower," "left," "right," "front," "rear," "top," "bottom," "inner," "outer," "middle," "vertical," "horizontal," "lateral," and "longitudinal" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. These terms are primarily for the purpose of better describing this application and its embodiments, and are not intended to limit the indicated device, element, or component to having a specific orientation, or to be constructed and operated in a specific orientation.

[0029] Furthermore, the terms "installation," "setup," "equipped with," "connection," "linking," and "socketing" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral structure; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium, or an internal connection between two devices, components, or parts. Those skilled in the art can understand the specific meaning of these terms in this application based on the specific circumstances.

[0030] A helicopter rotor blade folding strut fixing device uses circumferential and axial limiting pins on a crossbar to restrict the displacement of the fixing device, achieving reliable fixation between the folding fixing device and the fuselage structure. A ball joint extending from the fixing device mates with the inner spherical surface of the lower end of the rotor blade strut, and a quick-release pin secures the folding strut. Details are as follows:

[0031] A helicopter rotor blade folding strut fixing device includes a crossbar 100, a bushing 200, a circumferential limiting pin 300, an axial limiting pin 400, a ball joint 500, and a plug 600.

[0032] The bushing 200 is installed on the tail beam frame of the fuselage, and the crossbar 100 passes through the bushing and is connected to the fuselage structure. The overload of the blade can be transmitted to the fuselage frame through the blade support rod 700 and the crossbar.

[0033] The outer diameter of the crossbar 100 is the same as the inner diameter of the bushing 200 installed on the helicopter fuselage. During installation, the crossbar is inserted into the fuselage along the inner hole of the bushing 200. After installation, the exposed part of the crossbar is used to connect with the bottom end of the rotor strut 700.

[0034] The circumferential limiting pin 300 is installed on the crossbar and includes a limiting pin 301, a limiting pin sleeve 302, a handle 303, a handle sleeve 304, and a spring 305. After the crossbar is installed in place, the circumferential limiting pin is aligned with the circumferential limiting pin locking hole of the machine body and inserted to achieve circumferential locking of the crossbar.

[0035] The limiting pin sleeve 302 is fixed to the crossbar by rivets, providing the installation position for the circumferential limiting pin. The axis of the rivet forms a 90° angle with the thread connecting the center of the limiting pin 301 to the center of the limiting pin sleeve 302.

[0036] One end of the limiting pin 301 is provided with a shoulder to prevent it from coming out of the limiting pin sleeve 302, and the other end passes through the handle sleeve 304 and is connected to the handle 303 by a threaded connection.

[0037] One end of the handle sleeve 304 is fixed to one side of the limit pin sleeve by a threaded connection, and the other end is provided with a U-shaped groove. By lifting and rotating the handle 303, the handle can be fixed in two positions, and the circumferential limit pin can be fixed and released at the same time.

[0038] The spring 305 is fitted into the limiting pin 301, with one end limited by the shoulder of the limiting pin 301 and the other end limited by the handle sleeve 304. When the circumferential limiting pin is unlocked, the shoulder of the limiting pin 301 compresses the spring 305, and the handle 303 moves out of the U-shaped groove and rotates to fix it. When the circumferential limiting pin is locked, rotating the handle 303 into the U-shaped groove will automatically press the limiting pin into the mounting hole of the machine body, thus achieving automatic fixing of the circumferential limiting pin.

[0039] The axial limiting pin 400 is installed on the crossbar by interference fit. Its length is greater than the outer diameter of the crossbar. After installation, the exposed length on both sides is the same as the depth of the L-shaped groove in the bushing 200. The bushing 200 is provided with two L-shaped grooves. When the crossbar 100 is installed, it drives the axial limiting pin 400 to move linearly along the L-shaped groove and then rotates to the position, so that the crossbar can be fixed along its axial direction.

[0040] The spherical joint 500 is fixed to the crossbar 100 by bolts. The radius of the ball head is the same as the inner spherical surface of the lower joint of the folding strut 700. The diameter of the ball head support arm is the same as the U-shaped opening size of the lower joint of the folding strut 700. Both are smaller than the diameter of the ball head, which can ensure that the folding strut will not come out along the direction of the ball head support arm after installation. After the spherical joint is connected to the lower joint, a quick-release pin is inserted. The folding strut can rotate freely around the X and Y directions shown in the figure, which can compensate for the error of the inaccurate manual folding position of the blade.

[0041] The plug 600 is installed at the end of the crossbar to prevent foreign objects from entering during outdoor storage.

[0042] To ensure that the circumferential limiting pin can align with the quick-release pin hole on the machine body after the axial limiting pin rotates into position along the L-shaped groove, the following constraint relationship needs to be satisfied:

[0043] α=γ; β=θ; ξ=θ.

[0044] in,

[0045] α: The circumferential grooving angle of the L-shaped groove of the bushing. During installation, ensure that side A of α is in a horizontal position.

[0046] γ: The angle between the 500 cylindrical axis of the ball joint and the 400 cylindrical axis of the axial limiting pin;

[0047] β: The angle between the cylindrical axis of the spherical joint 500 and the cylindrical axis of the rivet mounted on the limit pin sleeve 302;

[0048] θ: The angle between the line connecting the center of the limiting pin 301 to the center of the limiting pin sleeve 302 and the vertical direction when the axis of the spherical joint cylinder is in a horizontal position;

[0049] ξ: The angle between the line connecting the center of the mounting hole of the bushing 200 on the machine body to the center of the locking hole of the axial limit pin and the vertical direction.

[0050] In use, insert the crossbar vertically into the helicopter frame along the sleeve until the axial limiting pin is flush with the end face of the sleeve. Rotate the crossbar so that the exposed parts on both sides of the axial limiting pin align with the L-shaped groove of the sleeve. Continue inserting the crossbar inward along the sleeve until it stops, then rotate clockwise until it stops. At this point, the circumferential limiting pin aligns with the limiting pin hole on the fuselage. Rotate the handle into the U-shaped groove of the handle sleeve. Under the action of the compression spring, the circumferential limiting pin automatically inserts into the circumferential limiting pin hole, thus fixing the crossbar. Align the inner ball surface of the lower connector of the folding strut with the spherical connector and insert it, then insert the quick-release pin to fix the folding strut.

[0051] The key points of this application are as follows:

[0052] 1. By setting an L-shaped slot, combined with circumferential and axial limiting pins, the fixing device can be quickly fixed to the machine body structure;

[0053] 2. By using a spherical joint to mate with the inner spherical surface, the folding strut can be connected to the fixing device while ensuring that the folding strut rotates around the ball head, thus compensating for the positional error of the blade folding.

[0054] The above description is merely a preferred embodiment of this application and is not intended to limit this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A helicopter rotor blade folding strut fixing device, characterized in that: The device includes: Crossbars, bushings, circumferential limit pins, axial limit pins, ball joints; The bushing is installed on the tail beam frame of the fuselage, and the crossbar passes through the bushing and is connected to the fuselage structure. The circumferential limit pin is installed on the crossbar. After the crossbar is installed in place, it is aligned with the quick-release pin hole of the machine body and inserted to achieve circumferential locking of the crossbar. The axial limiting pin is installed on the crossbar with an interference fit. Its length is greater than the outer diameter of the crossbar and it is used to fix the crossbar axially. The ball joint is bolted to the crossbar and is used to connect to the lower joint of the folding strut.

2. The apparatus according to claim 1, characterized in that: The inner wall of the bushing is symmetrically provided with two L-shaped grooves.

3. The apparatus according to claim 2, characterized in that: The circumferential limit pin includes a limit pin body, a limit pin sleeve, a handle, a handle sleeve, and a spring; The limit pin sleeve is fixed to the crossbar by rivets; One end of the limit pin is provided with a shoulder to prevent it from coming out of the limit pin sleeve, and the other end passes through the handle sleeve and is connected to the handle by threads. One end of the handle sleeve is fixed to one side of the limit pin sleeve by a threaded connection, and the other end is provided with a U-shaped groove. By lifting and rotating the handle, the handle can be fixed in two positions, and the circumferential limit pin can be fixed and released at the same time. The spring is sleeved on the limiting pin, with one end limited by the shoulder of the limiting pin and the other end limited by the handle sleeve. When the circumferential limiting pin is unlocked, the shoulder of the limiting pin drives the spring to compress, and the handle moves out of the U-shaped groove and rotates to fix it. When the circumferential limiting pin is locked, the handle is rotated into the U-shaped groove, and the compressed spring automatically presses the limiting pin into the mounting hole of the machine body, thereby realizing the automatic fixing of the circumferential limiting pin.

4. The apparatus according to claim 3, characterized in that: The length of the axial limiting pin is greater than the outer diameter of the crossbar. After installation, the exposed length on both sides is the same as the depth of the L-shaped groove in the bushing. When the crossbar is installed, the axial limiting pin moves linearly along the L-shaped groove and then rotates to the position, fixing the crossbar along its axial direction.

5. The apparatus according to claim 4, characterized in that: The ball head radius of the ball joint is the same as the inner spherical surface of the lower joint of the folding strut, and the diameter of the ball head arm is the same as the U-shaped opening size of the lower joint of the folding strut.

6. The apparatus according to claim 5, characterized in that: The device further includes: a plug; The cap is installed at the end of the crossbar to prevent foreign objects from entering during outdoor storage.

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