Mechanical emergency release device for landing gear electric actuator

Abstract

This invention provides a mechanical emergency unlocking device for a landing gear electric actuator, comprising a front cover and a rear cover connected to the cylinder body by screws; a slider is provided on the front and rear sides of the sliding lock sleeve, and both the front and rear covers are provided with guide grooves, with the sliders embedded in the guide grooves to provide horizontal guidance for the movement of the sliding lock sleeve, and also to transmit the force of the sliding lock sleeve to the entire sleeve; both the front and rear covers have a circular opening in the middle to facilitate the passage of a specially made screw nut after unlocking; the sliding lock sleeve and the specially made screw nut each have six locking grooves, the shape of which matches the lock cylinder, and when the sliding lock sleeve and the specially made screw nut are in contact, they can just wrap the lock cylinder within them. The locking grooves of the lock sleeve and the locking grooves of the nut are both semi-enclosed structures, which axially obstruct the lock cylinder; a roller is installed in the middle of the upper end of the sliding lock sleeve on both sides, and the lower side of the unlocking pin is machined into a bevel and rounded, so that the unlocking pin can smoothly enter the gap of the sliding lock sleeve under the action of the roller and the bevel.

Description

Technical Field

[0001] This invention belongs to the field of actuators and relates to a mechanical emergency unlocking device for a landing gear electric actuator. Background Technology

[0002] The aircraft landing gear is a core component during landing, and its proper extension and retraction directly determine the safety of the landing. The landing gear actuators are the power components that drive the landing gear. Under normal circumstances, their extension and retraction are electrically driven and controlled. To prevent the landing gear from failing to extend due to actuator failure caused by problems with the drive system or mechanical structure, an emergency unlocking function is usually added to the actuator. In the event of a complete failure of the main system, the actuator cylinder disengages from the power output section, forcibly releasing the landing gear to ensure a safe landing and improve aircraft reliability. However, existing aircraft landing gear actuator emergency unlocking devices suffer from problems such as complex structure, slow response, or still requiring a certain electro-hydraulic-pneumatic system for unlocking, making it difficult to meet emergency unlocking needs in extreme situations such as when electro-hydraulic-pneumatic systems are unavailable. Summary of the Invention

[0003] This application provides a mechanical emergency unlocking device for landing gear electric actuators, which can solve the problems of complex structure and slow response of existing aircraft landing gear actuator emergency unlocking devices.

[0004] Technical solution: A mechanical emergency unlocking device for a landing gear electric actuator, comprising a front cover 1, a rear cover 2, a cylinder 3, a screw 4, a friction pin sleeve 5, an unlocking pin 6, a spring 7, a guide groove 8, a sliding lock sleeve 9, a lock sleeve locking groove 10, a slider 11, a roller 12, a lock cylinder 13, a specially made lead screw nut 14, and a nut locking groove 15, wherein: The front cover 1 and the rear cover 2 are connected to the cylinder body 3 by screws 4. The sliding lock sleeve 9 has sliders 11 on the front and rear sides. The front cover 1 and the rear cover 2 are each provided with guide grooves 8. The sliders 11 are embedded in the guide grooves 8, which provide horizontal guidance for the movement of the sliding lock sleeve 9 and also allow the force of the sliding lock sleeve 9 to be transmitted to the entire sleeve. The front cover 1 and the rear cover 2 both have circular openings in the middle to facilitate the passage of the special screw nut 14 after unlocking. The sliding lock sleeve 9 and the special screw nut 14 are each provided with six locking grooves, the shape of which matches the lock cylinder 13. When the sliding lock sleeve 9 and the special screw nut 14 are in contact, they can just wrap the lock cylinder 13. The lock sleeve locking groove 10 and the nut locking groove 15 are both semi-enclosed structures, which axially block the lock cylinder 13 and can transmit axial movement. The upper middle of the sliding lock sleeves 9 on both sides is equipped with rollers 12. The lower side of the unlocking pin 6 is machined into a bevel and rounded. Under the action of the rollers 12 and the bevel, the unlocking pin can smoothly enter the gap of the sliding lock sleeve 9.

[0005] In summary, this application provides a mechanical emergency unlocking device for landing gear electric actuators. It achieves locking and emergency unlocking entirely through a mechanical structure, avoiding the need for additional electro-hydraulic / pneumatic systems. Even under extreme conditions where electro-hydraulic systems are unavailable, it still possesses unlocking functionality. The device features a simple structure, high reliability, and a purely mechanical transmission structure, comprising only core components such as the sleeve body, lock cylinder, and sliding sleeve. It lacks complex piping or electronic control components, resulting in a low failure rate and adaptability to the harsh operating conditions of the aerospace industry. The device offers rapid response; unlocking is immediately triggered by squeezing the unlocking pin with a tool, significantly improving response speed compared to electric unlocking systems and meeting the rapid unlocking requirements in emergency situations. Maintenance is simple; no regular maintenance of hydraulic oil or electrical circuits is required. All components are modularly integrated and replaceable. Attached Figure Description

[0006] Figure 1 This is a schematic diagram of the structure of a mechanical emergency unlocking device for a landing gear electric actuator provided by the present invention; Figure 2 This is an exploded view of a mechanical emergency unlocking device for a landing gear electric actuator provided by the present invention; Figure 3 This is a structural cross-sectional view of a mechanical emergency unlocking device for a landing gear electric actuator provided by the present invention; Figure 4 yes Figure 2 A schematic diagram of the sliding locking sleeve; Figure 5 yes Figure 2 A schematic diagram of a specially made lead screw nut; Figure 6 yes Figure 2 A schematic diagram of the central lock cylinder; Figure 7 yes Figure 2 A schematic diagram of the front cover; Figure 8 yes Figure 2 A diagram illustrating the unlocking pin; Among them: 1-front cover, 2-rear cover, 3-cylinder body, 4-screw, 5-friction pin sleeve, 6-unlocking pin, 7-spring, 8-guide groove, 9-sliding lock sleeve, 10-lock sleeve lock groove, 11-slider, 12-roller, 13-lock cylinder, 14-special lead screw nut, 15-nut lock groove. Detailed Implementation

[0007] This application presents a sleeve-shaped aircraft landing gear electric actuator with a non-electro-hydraulic / pneumatic emergency unlocking device that achieves physical unlocking through a purely mechanical means. Under normal circumstances, the symmetrical sliding lock sleeves on both sides of the sleeve press the lock core against the corresponding lock groove on the lead screw nut through springs. The actuator cylinder is connected to the outside of the sleeve, realizing the locking and motion transmission of the actuator cylinder and the lead screw nut. Once the actuator experiences an electrical or mechanical failure, the unlocking pin in the pin chamber on the upper part of the sleeve is pressed by a tool, causing the unlocking pin to move downward along the pin chamber. The unlocking pin enters the gap between the two sliding lock sleeves through its inclined surface and the upper roller of the sliding lock sleeve, pressing the sliding lock sleeve to move laterally along the front and rear sliding grooves, driving the lock core to leave the lead screw nut and successfully disengage from the lead screw. Subsequently, the landing gear extends under its own weight, realizing the emergency unlocking function in the absence of energy through a purely physical means.

[0008] Example 1 like Figure 1-3 As shown, this application provides a mechanical emergency unlocking device for a landing gear electric actuator, including a front cover 1, a rear cover 2, a cylinder 3, a screw 4, a friction pin sleeve 5, an unlocking pin 6, a spring 7, a guide groove 8, a sliding lock sleeve 9, a lock sleeve locking groove 10, a slider 11, a roller 12, a lock cylinder 13, a specially made lead screw nut 14, and a nut locking groove 15, wherein: The front cover 1 and rear cover 2 are connected to the cylinder body 3 by screws 4; the sliding lock sleeve 9 has a total of 12 sliders 11 on its front and rear sides, and the front cover 1 and rear cover 2 each have 6 guide grooves 8. The sliders 11 are embedded in the guide grooves 8, providing horizontal guidance for the movement of the sliding lock sleeve 9, and also allowing the force on the sliding lock sleeve 9 to be transmitted to the entire sleeve; the front cover 1 and rear cover 2 each have a circular opening in the middle to facilitate the passage of the special lead screw nut 14 after unlocking; the sliding lock sleeve 9 and the special lead screw nut 14 each have six locking grooves, the shape of which is... The shape matches the lock cylinder 13. When the sliding lock sleeve 9 is in contact with the special lead screw nut 14, it can just wrap the lock cylinder 13. The lock sleeve groove 10 and the nut groove 15 are both semi-enclosed structures, which block the lock cylinder 13 axially and can transmit axial movement. Rollers 12 are installed in the middle of the upper end of the sliding lock sleeves 9 on both sides. The lower side of the unlocking pin 6 is processed into a bevel and rounded. Under the action of the roller 12 and the bevel, the unlocking pin can smoothly enter the gap of the sliding lock sleeve 9 without impact or collision that would prevent the sliding lock sleeve 9 from being squeezed open.

[0009] Specifically, such as Figure 7 As shown, the front cover 1 is a circular plate structure with an inner hole, which is used for the sliding lock sleeve 9 and the special lead screw nut 14. There are 4 evenly distributed through holes on the cover plate panel, which are connected to the cylinder body 3 by 4 screws 4. The cover plate panel has 6 parallel rectangular guide grooves 8, of which the central axis of the two middle guide grooves 8 passes through the center of the cover plate circle, and the other 4 guide grooves 8 are symmetrically distributed above and below the two middle guide grooves 8. The structure of the rear cover 2 is the same as that of the front cover 1.

[0010] Specifically, such as Figure 2 , Figure 3 As shown, the cylinder body 3 is a cylindrical structure with four threaded holes on its front and rear end faces for connecting with the front cover 1 and the rear cover 2. There are two small protrusions on the inner wall along the middle of the axis for installing the spring 7. There is a friction pin sleeve 5 with a rounded corner and a groove in the middle on the outer wall along the middle of the axis, which is approximately rectangular and used to place the unlocking pin 6.

[0011] Specifically, such as Figure 2 , Figure 3 As shown, the friction pin sleeve 5 is integrated on the cylinder body 3. It is an approximately rectangular cylindrical structure with rounded corners and a groove in the middle. The central axis of the cylindrical structure is perpendicular to the axis of the cylinder body 3.

[0012] Specifically, such as Figure 8 As shown, the unlocking pin 6 is an approximately rectangular post with rounded corners. The lower side of the post is machined into a bevel and rounded. There is a protruding limiting ring in the middle section of the post.

[0013] Specifically, such as Figure 7 As shown, the guide groove 8 is integrated on the front cover 1 or the rear cover 2. It is a rectangular groove, and there are 6 guide grooves 8 on the front cover 1 and the rear cover 2 respectively.

[0014] Specifically, such as Figure 4 As shown, the sliding lock sleeve 9 is a semi-circular cylindrical structure with three horizontal arc-shaped lock sleeve grooves 10 evenly distributed on the cylindrical wall, three horizontally distributed elongated sliders 11 on the cylindrical end face, and a cylinder with a roller 12 installed in the middle of the upper end of the cylinder.

[0015] Specifically, such as Figure 4 As shown, the lock sleeve groove 10 is an arc-shaped groove, and three of them are integrated on the sliding lock sleeve 9.

[0016] Specifically, such as Figure 4 As shown, slider 11 is a long strip slider, which is integrated on the sliding lock sleeve 9.

[0017] Specifically, such as Figure 3 , Figure 4 As shown, the roller 12 is a long cylindrical structure and is installed on the cylinder at the middle of the upper end of the sliding lock sleeve 9.

[0018] Specifically, such as Figure 6 As shown, the lock cylinder 13 has a rectangular cylindrical structure.

[0019] Specifically, such as Figure 5 As shown, the special lead screw nut 14 is a lead screw nut with three horizontal, elongated, arc-shaped nut locking grooves 15 distributed on the left and right sides of the nut's cylindrical wall.

[0020] Specifically, such as Figure 5As shown, the nut locking groove 15 is a horizontal, elongated, arc-shaped groove integrated into the specially designed lead screw nut 14.

[0021] Specifically, such as Figure 4 , 7 As shown, the sliding lock sleeve 9 has a total of 12 sliders 11 on the front and rear sides. The front cover 1 and the rear cover 2 each have 6 guide grooves 8. The sliders 11 are embedded in the guide grooves 8, which provide horizontal guidance for the movement of the sliding lock sleeve 9 and also allow the force on the sliding lock sleeve 9 to be transmitted to the entire sleeve. The front cover 1 and the rear cover 2 each have a circular opening in the middle to facilitate the passage of the specially made lead screw nut 14 after unlocking.

[0022] Specifically, such as Figure 3 , 4 As shown in Figures 5 and 6, the sliding lock sleeve 9 and the special lead screw nut 14 each have six locking grooves, the shape of which matches the lock cylinder 13. When the sliding lock sleeve 9 and the special lead screw nut 14 are in contact, they can just wrap the lock cylinder 13. The lock sleeve groove 10 and the nut groove 15 are both semi-enclosed structures, which axially block the lock cylinder 13 and transmit axial movement.

[0023] Specifically, such as Figure 4 , 8 As shown, a roller 12 is installed in the middle of the upper end of the sliding lock sleeves 9 on both sides. The lower side of the unlocking pin 6 is machined into a bevel and rounded. Under the action of the roller 12 and the bevel, the unlocking pin can smoothly enter the gap of the sliding lock sleeve 9 without impact or collision, which would prevent the sliding lock sleeve 9 from being squeezed open.

[0024] Specifically, such as Figure 3 , 4As shown in Figures 7 and 8, under normal circumstances, the sliding lock sleeve 9, under the thrust of the spring 7, locks the lock cylinder 13 in the lock sleeve groove 10 and the nut groove 15. When the specially designed lead screw nut 14 rotates with the lead screw shaft to make linear motion, it generates an axial thrust on the lock cylinder 13. The lock cylinder 13 transmits the force to the sliding lock sleeve 9, and then to the entire emergency unlocking device, causing the actuator cylinder to move and realizing the locking function between the actuator cylinder and the lead screw. The inner side of the friction pin sleeve 5 is made of a high-friction coefficient material, generating static friction on the unlocking pin 6, preventing it from sliding down under normal circumstances due to gravity. However, if an electrical or mechanical failure causes the lead screw to fail and the special lead screw nut 14 loses power and cannot move, the exposed part of the unlocking pin 6 is compressed. The unlocking pin 6 is impacted and slides down, smoothly entering the gap of the sliding lock sleeve 9 under the action of the inclined plane and roller 12. This compresses the sliding lock sleeve 9, which then moves horizontally to both sides under the action of the slider 11 and guide groove 8, carrying the lock core 13 out of the nut locking groove 15 of the special lead screw nut 14. At this point, the special lead screw nut 14 no longer obstructs the sleeve's displacement, and the landing gear extends under its own weight, achieving the emergency unlocking function. The unlocking pin 6 has a protruding limiting ring in the middle section, located in a cavity within the friction pin sleeve 5. During compression, the lowest part of the cavity obstructs the limiting ring, preventing the unlocking pin 6 from impacting the special lead screw nut 14.

[0025] In summary, this application provides an emergency unlocking device for an aircraft landing gear electric actuator without electro-hydraulic / pneumatic power. It comprises a front cover, rear cover, cylinder, screw, friction pin sleeve, unlocking pin, spring, guide groove, sliding lock sleeve, lock sleeve locking groove, slider, roller, lock cylinder, specially designed lead screw nut, and nut locking groove. These modules cooperate to achieve locking and emergency unlocking functions. The emergency unlocking actuator, composed of the friction pin sleeve, unlocking pin, sliding lock sleeve, spring, slider, guide groove, roller, lock cylinder, and specially designed lead screw nut, normally operates with the spring compressed, applying a thrust to the sliding lock sleeves on both sides, causing them to lock the lock cylinder within the specially designed locking groove of the lead screw nut, thus achieving locking. If the lead screw fails, it compresses the unlocking pin, causing it to enter the gap between the two sliding lock sleeves, pushing the two sliding sleeves horizontally under the guidance of the fixed slider and guide sleeve, separating the lock cylinder from the lead screw nut. The entire unlocking process is achieved by a purely mechanical structure and remains effective even in the absence of electro-hydraulic / pneumatic power. The inner wall of the friction pin sleeve is made of a high-friction coefficient material, preventing the unlocking pin from sliding down automatically under natural conditions. A limit ring is set in the middle section of the unlocking pin, located in the concave cavity of the middle section of the friction pin sleeve, which plays a limiting role, preventing the unlocking pin from hitting the nut after compression. Twelve sliders are fixedly connected to both sides of the sliding lock sleeve. The sliders are embedded in the guide grooves opened at corresponding positions on the front and rear covers, ensuring that the sliding lock sleeve will only move horizontally after being compressed.

Claims

1. A mechanical emergency release device for an electrically operated landing gear actuator, characterized in that Includes a front cover (1), a rear cover (2), a cylinder body (3), screws (4), friction pin sleeves (5), unlocking pins (6), springs (7), guide grooves (8), sliding lock sleeves (9), lock sleeve grooves (10), sliders (11), rollers (12), lock cylinders (13), special lead screw nuts (14), and nut lock grooves (15), among which: The front cover (1) and the rear cover (2) are connected to the cylinder body (3) by screws (4); the sliding lock sleeve (9) is provided with sliders (11) on the front and rear sides, and the front cover (1) and the rear cover (2) are respectively provided with guide grooves (8). The sliders (11) are embedded in the guide grooves (8) to provide horizontal guidance for the movement of the sliding lock sleeve (9), and at the same time, the force of the sliding lock sleeve (9) can be transmitted to the entire sleeve; the front cover (1) and the rear cover (2) are both provided with circular openings in the middle to facilitate the passage of the special screw nut (14) after unlocking; the sliding lock sleeve (9) and the special screw nut (14) 14) Each has six locking slots, the shape of which matches the lock cylinder (13). When the sliding lock sleeve (9) is in contact with the special lead screw nut (14), it can just wrap the lock cylinder (13) in it. The lock sleeve locking slot (10) and the nut locking slot (15) are both semi-enclosed structures, which block the lock cylinder (13) axially and can transmit axial movement. Rollers (12) are installed in the middle of the upper end of the sliding lock sleeves (9) on both sides. The lower side of the unlocking pin (6) is processed into a bevel and rounded. Under the action of the roller (12) and the bevel, the unlocking pin can smoothly enter the gap of the sliding lock sleeve (9).

2. The apparatus of claim 1, wherein, The front cover (1) is a circular plate structure with an inner hole, which is used for the sliding lock sleeve (9) and the special screw nut (14). There are 4 evenly distributed through holes on the cover plate panel, which are connected to the cylinder body (3) by 4 screws (4). The cover plate panel has 6 parallel rectangular guide grooves (8), of which the central axis of the two middle guide grooves (8) passes through the center of the cover plate circle, and the other 4 guide grooves (8) are symmetrically distributed above and below the two middle guide grooves (8). The structure of the rear cover (2) is the same as that of the front cover (1).

3. The apparatus of claim 1, wherein, The cylinder body (3) is a cylindrical structure with four threaded holes on its front and rear cylinder end faces for connecting with the front cover (1) and the rear cover (2). There are two small protrusions on the inner wall along the middle of the axis for installing the spring (7). There is a friction pin sleeve (5) with a rounded corner and a groove in the middle on the outer wall along the middle of the axis, which is approximately rectangular and used to place the unlocking pin (6).

4. The apparatus of claim 1, wherein, The friction pin sleeve (5) is integrated on the cylinder body (3). It is an approximately rectangular cylindrical structure with rounded corners and a groove in the middle. The central axis of the cylindrical structure is perpendicular to the axis of the cylinder body (3).

5. The apparatus of claim 1, wherein, The guide groove (8) is integrated on the front cover (1) or the rear cover (2). It is a rectangular groove. There are 6 guide grooves (8) on the front cover (1) and the rear cover (2).

6. The apparatus of claim 1, wherein, The sliding lock sleeve (9) is a semi-circular cylindrical structure with three horizontal arc-shaped lock sleeve grooves (10) evenly distributed on the cylinder wall, three horizontally distributed long strip sliders (11) on the cylinder end face, and a cylinder with a roller (12) installed in the middle of the upper end of the cylinder.

7. The apparatus of claim 1, wherein, The sliding lock sleeve (9) has a total of 12 sliders (11) on the front and back sides. The front cover (1) and the rear cover (2) each have 6 guide grooves (8). The sliders (11) are embedded in the guide grooves (8) to provide horizontal guidance for the movement of the sliding lock sleeve (9) and also to transmit the force of the sliding lock sleeve (9) to the entire sleeve. The front cover (1) and the rear cover (2) each have a circular opening in the middle to facilitate the passage of the specially made screw nut (14) after unlocking.

8. The apparatus of claim 1, wherein, The sliding lock sleeve (9) and the special lead screw nut (14) each have six locking grooves, the shape of which matches the lock cylinder (13). When the sliding lock sleeve (9) and the special lead screw nut (14) are in contact, they can just wrap the lock cylinder (13) inside. The lock sleeve groove (10) and the nut groove (15) are both semi-enclosed structures, which block the lock cylinder (13) axially and transmit axial movement.

9. The apparatus according to claim 1, characterized in that, Rollers (12) are installed in the middle of the upper end of the sliding lock sleeves (9) on both sides. The lower side of the unlocking pin (6) is processed into a bevel and rounded. Under the action of the roller (12) and the bevel, the unlocking pin can smoothly enter the gap of the sliding lock sleeve (9) without impact or collision, which would prevent the sliding lock sleeve (9) from being squeezed open.

10. The apparatus according to claim 1, characterized in that, Under normal circumstances, the sliding lock sleeve (9) holds the lock cylinder (13) in the lock sleeve groove (10) and the nut groove (15) under the thrust of the spring (7). When the special lead screw nut (14) rotates with the lead screw shaft to make linear motion, it generates an axial thrust on the lock cylinder (13). The lock cylinder (13) transmits the force to the sliding lock sleeve (9), and then to the entire emergency unlocking device, driving the actuator cylinder to move and realizing the locking function between the actuator cylinder and the lead screw. The inner side of the friction pin sleeve (5) is made of a high friction coefficient material, which generates static friction on the unlocking pin (6), so that the unlocking pin (6) will not slide down due to gravity under normal circumstances. Once an electrical or mechanical failure causes the lead screw to fail and the special lead screw nut (14) loses power and cannot move, the exposed part of the unlocking pin (6) is squeezed. The unlocking pin (6) is pushed down and smoothly squeezed into the gap of the sliding lock sleeve (9) under the action of the inclined plane and the roller (12). The sliding lock sleeve (9) is pressed and moves horizontally to both sides under the action of the slider (11) and the guide groove (8), carrying the lock core (13) away from the nut lock groove (15) of the special lead screw nut (14). At this time, the special lead screw nut (14) will no longer obstruct the sleeve displacement. Then, the landing gear extends under its own weight, realizing the emergency unlocking function. There is a protruding limiting ring in the middle section of the unlocking pin (6), which is located in a cavity inside the friction pin sleeve (5). When squeezed, the lowest part of the cavity will obstruct the limiting ring to prevent the unlocking pin (6) from impacting the special lead screw nut (14).

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