General mechanical energy taking device and braking system of large aircraft

Abstract

The invention relates to the technical field of brake systems of large aircrafts, in particular to a universal mechanical energy taking device and a brake system of a large aircraft. The mechanical energy taking device comprises an acceleration bull gear, an acceleration pinion, a constant-speed driving gear, an acceleration output shaft, a constant-speed driven gear and a constant-speed output shaft, the acceleration pinion and the constant-speed driving gear are sequentially and fixedly arranged on the acceleration output shaft in a sleeving manner, the constant-speed driven gear is fixedly arranged on the constant-speed output shaft in a sleeving manner, the acceleration pinion is internally meshed with the acceleration bull gear, and the acceleration bull gear is internally meshed with the constant-speed driven gear; and the constant-speed driving gear and the constant-speed driven gear are externally meshed, are fixed on an aircraft hub through a step cylindrical pin on the acceleration bull gear, and are fixed in a brake actuator through bearings on two output shafts. Kinetic energy of high-speed rotation of the airplane wheels can be extracted and supplied to the hydraulic pump through the inner meshing acceleration gear set and the outer meshing constant-speed gear set, the hydraulic pumps are arranged to selectively install the two output shafts, the hydraulic pumps of the same type can be installed and used on the left wheel and the right wheel, and the purpose of generalization is achieved.

Description

Technical Field

[0001] This invention relates to the field of braking system technology for large aircraft, specifically to a universal mechanical energy harvesting device and braking system for large aircraft. Background Technology

[0002] Aircraft braking systems are a crucial component in ensuring the braking and stopping of modern aircraft. Currently, aircraft braking systems generally rely on a centralized hydraulic power source from the main engine, which is transmitted to the brake actuators through dense, long pipelines. This presents challenges such as numerous hydraulic components, complex and difficult pipeline layout, heavy weight, and potential leaks. Electric brakes, on the other hand, suffer from issues such as high motor heat generation, difficulty in redundancy configuration, and low maturity. Self-powered braking devices, however, recover and utilize the energy dissipated by the aircraft wheels during the braking process. They convert the kinetic energy of the wheels' high-speed rotation during landing into hydraulic energy, which is directly supplied to the brake actuators to complete the aircraft's braking function, demonstrating promising application prospects.

[0003] Therefore, designing a mechanical energy harvesting mechanism within the extremely limited internal space of the aircraft wheels to extract the mechanical energy generated by the high-speed rotation and torque of the wheels during landing and supply it to the hydraulic pump is a pressing issue. Furthermore, ensuring the mechanical energy harvesting mechanism is adaptable to different wheel hubs and improving its versatility is also crucial. Summary of the Invention

[0004] To address the problems of existing technologies, this invention proposes a universal mechanical energy harvesting device and braking system for large aircraft.

[0005] A universal mechanical energy harvesting device for large aircraft includes: a large acceleration gear, a small acceleration gear, a constant velocity driving gear, an acceleration output shaft, a constant velocity driven gear, and a constant velocity output shaft. The small acceleration gear and the constant velocity driving gear are sequentially sleeved and fixed on the acceleration output shaft, and the constant velocity driven gear is sleeved and fixed on the constant velocity output shaft. The small acceleration gear meshes internally with the large acceleration gear, and the constant velocity driving gear meshes externally with the constant velocity driven gear. Multiple stepped cylindrical pins penetrate the circumferential surface of the large acceleration gear.

[0006] Furthermore, two slots with a racetrack-shaped cross-section are formed by symmetrically cutting off the upper and lower parts and the left and right parts on the acceleration output shaft, which are used to install the acceleration pinion and the constant velocity drive gear, respectively. A slot with a racetrack-shaped cross-section is formed by symmetrically cutting off the upper and lower parts on the constant velocity output shaft, which is used to install the constant velocity driven gear.

[0007] Furthermore, a first limiting sleeve is installed on the side of the constant velocity driving gear and sleeved on the acceleration output shaft, and a second limiting sleeve is installed on the side of the constant velocity driven gear and sleeved on the constant velocity output shaft.

[0008] Furthermore, one end of both the acceleration output shaft and the constant speed output shaft is secured with a self-locking nut.

[0009] A braking system for a large aircraft includes an aircraft hub, a landing gear axle, and a brake actuator. The aircraft hub is mounted on the landing gear axle, and the brake actuator is installed on the side of the aircraft hub. It also includes the aforementioned mechanical energy harvesting device for the large aircraft. A stepped cylindrical pin is inserted into a pin hole in the aircraft hub, and a large acceleration gear is fixedly connected to the aircraft hub via screws. A small bearing and a large bearing are respectively mounted on the acceleration output shaft and the constant velocity output shaft, and the acceleration output shaft and the constant velocity output shaft are positioned within the brake actuator via the small bearing and the large bearing.

[0010] Furthermore, it also includes a bearing support, in which the large bearing is fixed and positioned with the brake actuator via the bearing support.

[0011] Furthermore, the adjacent sides of the two bearing support seats are straight edges that are parallel to each other.

[0012] Furthermore, a retaining ring is installed on the outer side of the bearing support, and the outer diameter of the retaining ring is larger than the outer diameter of the bearing support.

[0013] Furthermore, the small bearing on the acceleration output shaft is located between the acceleration pinion and the constant velocity drive gear, while the large bearing on the acceleration output shaft is located on the other side of the constant velocity drive gear; the position of the small bearing on the constant velocity output shaft corresponds to the position of the small bearing on the acceleration output shaft, and the position of the large bearing corresponds to the position of the large bearing on the acceleration output shaft.

[0014] This invention extracts the kinetic energy (torque and speed) from the high-speed rotation of aircraft wheels and supplies it to a hydraulic pump through a set of internally meshing accelerating gears and a set of externally meshing constant velocity gears. Furthermore, for aircraft wheels with different steering directions, the hydraulic pumps for the left and right wheels can be optionally asynchronously mounted on either the accelerating or constant velocity output shaft, allowing the same type of hydraulic pump (with the same steering direction) to be used on both wheels, achieving universal mechanical energy extraction. This invention features a compact structure, high power-to-weight ratio, and high reliability, making it suitable for self-powered braking systems in any large aircraft, as well as in the automotive and industrial machinery fields. Depending on the space constraints of the installation location, the transmission ratio and center distance can be adjusted by changing the number of teeth and module of the two gear sets to meet the output speed requirements and installation needs. Attached Figure Description

[0015] The embodiments of the present invention will be further described below with reference to the accompanying drawings, wherein:

[0016] Figure 1 A three-dimensional schematic diagram of a generalized mechanical energy harvesting device for a large aircraft in the embodiment is shown.

[0017] Figure 2 A cross-sectional view of a generalized mechanical energy harvesting device for a large aircraft in the embodiment is shown.

[0018] Figure 3 A cross-sectional view of the braking system of a large aircraft in the embodiment is shown;

[0019] Figure 4 A partial structural schematic diagram of the universal mechanical energy harvesting device for large aircraft in the embodiment is shown.

[0020] 1-Stepped cylindrical pin; 2-Accelerating large gear; 3-Screw; 4-First self-locking nut; 5-Accelerating small gear; 6-First small bearing; 7-First limiting sleeve; 8-Constant velocity driving gear; 9-First bearing support; 10-First large bearing; 11-Accelerating output shaft; 12-Second self-locking nut; 13-Second small bearing; 14-Second limiting sleeve; 15-Constant velocity driven gear; 16-Second bearing support; 17-Retaining ring; 18-Second large bearing; 19-Constant velocity output shaft; 20-Aircraft wheel hub; 21-Landing gear wheel axle; 22-Mechanical energy harvesting device; 23-Brake actuator. Detailed Implementation

[0021] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0022] In one embodiment, such as Figure 3 As shown, a braking system for a large aircraft includes an aircraft hub 20, a landing gear axle 21, and a brake actuator 23. The aircraft hub 20 is mounted on the landing gear axle 21, and the brake actuator 23 is installed on the side of the aircraft hub 20. It also includes a mechanical energy harvesting device 22 for the large aircraft.

[0023] Mechanical energy harvesting device 22 of large aircraft, such as Figure 2As shown, the system includes: a large acceleration gear 2, a small acceleration gear 5, a constant velocity driving gear 8, an acceleration output shaft 11, a constant velocity driven gear 15, and a constant velocity output shaft 19. The small acceleration gear 5 and the constant velocity driving gear 8 are sequentially fitted and fixed on the acceleration output shaft 11, and the constant velocity driven gear 15 is fitted and fixed on the constant velocity output shaft 19. The small acceleration gear 5 meshes internally with the large acceleration gear 2, and the constant velocity driving gear 8 meshes externally with the constant velocity driven gear 15. Multiple stepped cylindrical pins 1 penetrate the circumference of the large acceleration gear 2. The acceleration output shaft 11 has two slots symmetrically cut away from its upper and lower sections and left and right sections to form a racetrack-shaped cross-section, used to fit and install the small acceleration gear 5 and the constant velocity driving gear 8, respectively. The constant velocity output shaft 19 has one slot symmetrically cut away from its upper and lower sections to form a racetrack-shaped cross-section, used to fit and install the constant velocity driven gear 15. The racetrack-shaped slot matches the inner diameter of the small acceleration gear 5, the constant velocity driving gear 8, and the constant velocity driven gear 15, and limits the gear movement.

[0024] The Φa hole of the accelerator gear 2 is matched with the corresponding diameter of the hub, and the hole and diameter are matched for installation and positioning. The stepped cylindrical pin 1 of the accelerator gear 2 is inserted into the corresponding pin hole on the aircraft hub. There are at least 6 stepped cylindrical pins 1, which are used to transmit torque. The accelerator gear 2 is fixedly connected to the aircraft hub 20 by screws 3. The first small bearing 6 and the first large bearing 10 are sleeved on the accelerator output shaft 11. The first large bearing 10 is fixed in the first bearing support 9. The accelerator output shaft 11 is installed and positioned in the brake actuator 23 through the first small bearing 6 and the first bearing support 9. The accelerator pinion 5 and the constant velocity drive gear 8 are both installed on the accelerator output shaft 11 by the runway-shaped locking and limiting mechanism. The first small bearing 6 on the accelerator output shaft 11 is located between the accelerator pinion 5 and the constant velocity drive gear 8. The first large bearing 10 on the accelerator output shaft 11 is located on the other side of the constant velocity drive gear 8. Figure 2 (As shown on the right), a first limiting sleeve 7 is installed between the first small bearing 6 and the constant velocity drive gear 8, and is sleeved on the acceleration output shaft 11. The constant velocity drive gear 8 is also axially limited by the acceleration output shaft 11 and the first limiting sleeve 7. The first small bearing 6 and the first large bearing 10 are axially limited by parts such as the shoulder of the acceleration output shaft 11, the first limiting sleeve 7, the shoulder of the bearing support seat 9, and the shoulder of the brake actuator 23. The other end of the acceleration output shaft 11 is fastened by the first self-locking nut 4. Figure 2As can be seen, from left to right, the acceleration output shaft 11 is equipped with: a first self-locking nut 4; an acceleration pinion 5 located in the first racetrack-shaped locking position; a first small bearing 6 and a first limiting sleeve 7 simultaneously located on the right side of the normally shaped shaft; a constant velocity drive gear 8 located in the second racetrack-shaped locking position; and a first large bearing 10 located on the far right. The acceleration pinion 5, the constant velocity drive gear 8, and the acceleration output shaft 11 are all circumferentially and axially limited by the racetrack-shaped locking positions.

[0025] Similarly, the position of the second small bearing 13 on the constant velocity output shaft 19 corresponds to the position of the first small bearing 6 on the acceleration output shaft 11, and the position of the second large bearing 18 corresponds to the position of the first large bearing 10 on the acceleration output shaft 11. A second limiting sleeve 14 is installed on the left side of the constant velocity driven gear 15 and sleeved on the constant velocity output shaft 19. The constant velocity driven gear 15 is axially limited by the constant velocity output shaft 19 and the second limiting sleeve 14. The constant velocity output shaft 19 is installed and positioned in the brake actuator 23 by the second small bearing 13 and the second bearing support 16. The second small bearing 13 and the second large bearing 18 are axially limited by the shoulder of the constant velocity output shaft 19, the second limiting sleeve 14, the shoulder of the second bearing support 16, the shoulder of the brake actuator 23, and other parts. The other end is fastened by the second self-locking nut 12. Figure 2 As can be seen, the constant velocity output shaft 19 is equipped with the following components from left to right: a second self-locking nut 12, a second small bearing 13, a second limiting sleeve 14, a constant velocity driven gear 15 fitted onto a racetrack-shaped slot, and a second large bearing 18. The constant velocity driven gear 15 and the constant velocity output shaft 19 are circumferentially and axially limited by the racetrack-shaped slot.

[0026] The first bearing support 9 and the second bearing support 16 are both annular structures with a portion cut off. The inner diameter of the annular structure matches the outer diameter of the large bearing. The adjacent sides of the first bearing support 9 and the second bearing support 16 are parallel straight edges, which can contact each other or have an appropriate gap. This shape structure is beneficial to reducing the distance between the two shafts, and the two support seats can be limited by a retaining ring. The first bearing support 9 and the second bearing support 16 are axially limited by a retaining ring 17. The axis of the retaining ring 17 can be the axis of the first bearing support 9 or the axis of the second bearing support 16. The outer diameter of the retaining ring 17 is larger than the outer diameter of the support seat. The first limiting sleeve 7 and the second limiting sleeve 14 are used for axial limiting of the constant velocity driving gear 8 and the constant velocity driven gear 15, respectively.

[0027] During installation, first insert the stepped cylindrical pin 1 of the accelerator gear 2 into the corresponding pin hole of the aircraft hub 20. The Φa hole of the accelerator gear 2 matches the corresponding diameter of the hub for installation and positioning. The torque is transmitted through the stepped cylindrical pin 1, and the accelerator gear 2 is fixedly connected to the aircraft hub 20 by screws 3.

[0028] Install the second large bearing 18 onto the constant velocity output shaft 19 from left to right. Then, insert the constant velocity output shaft 19 with the second large bearing 18 into the second bearing support 16 from right to left. Insert the constant velocity driven gear 15 into the constant velocity output shaft 19. The two are circumferentially and axially limited by the racetrack-shaped locking mechanism of the constant velocity output shaft 19. Then, install the second limiting sleeve 14. Then, insert the whole assembly into the brake actuator 23 from right to left. Install the second small bearing 13 from the left end. Adjusting shims can also be installed. Finally, install the second self-locking nut 12.

[0029] Similarly, following the same method and steps, the first large bearing 10 is installed on the acceleration output shaft 11 from left to right. Then, the acceleration output shaft 11 with the first large bearing 10 is inserted into the first bearing support 9 from right to left. The constant velocity drive gear 8 is inserted into the acceleration output shaft 11. The two are circumferentially and axially limited by the racetrack-shaped locking mechanism of the acceleration output shaft 11. Then, the first limiting sleeve 7 is installed. The whole assembly is then inserted into the brake actuator 23 from right to left. The first small bearing 6 is installed from the left end, followed by the acceleration pinion 5. The acceleration pinion 5 and the acceleration output shaft 11 are circumferentially limited by the racetrack-shaped locking mechanism. Adjusting shims are installed as needed. Finally, the first self-locking nut 4 is installed. The retaining ring 17 is installed in the corresponding groove of the brake actuator 23 to restrict the axial movement of the acceleration output shaft 11 and the constant velocity output shaft 19. The acceleration pinion 5 meshes internally with the acceleration large gear 2, and the constant velocity drive gear 8 meshes externally with the constant velocity driven gear 15.

[0030] Let the number of teeth of the large accelerator gear 2 be Z1, the number of teeth of the small accelerator gear 5 be Z2, and the module be m1; the number of teeth of the constant velocity driving gear 8 be Z3; the number of teeth of the constant velocity driven gear 15 be Z4, and the module be m2; and the rotational speed of the aircraft hub 20 be n. a The speed of the accelerated output shaft 11 is n b The rotational speed of the constant velocity output shaft 19 is n. c The large accelerator gear 2 and the small accelerator gear 5 form an internal meshing gear set with a transmission ratio of Center distance is The constant velocity driving gear 8 and the constant velocity driven gear 15 form a constant velocity external meshing gear set, with a transmission ratio of... Center distance is

[0031] When an aircraft taxis or lands, and the landing gear touches the ground, the enormous kinetic energy is converted into the mechanical energy of the wheels, resulting in a circumferential rotational motion with a certain speed and torque, the speed being n. a Since the large acceleration gear 2 is rigidly connected to the aircraft wheel hub 20 via the stepped cylindrical pin 1, the large acceleration gear 2 synchronously rotates in a circumferential direction at a speed of n. aThe rotational speed is transmitted to the acceleration output shaft 11 via the accelerator pinion 5. Both the accelerator pinion 5 and the constant velocity drive gear 8 are rigidly connected to the acceleration output shaft 11 via locking mechanisms, ensuring equal rotational speeds.

[0032] The constant velocity driving gear 8 transmits its rotational speed to the constant velocity driven gear 15. The constant velocity driven gear 15 is rigidly connected to the constant velocity output shaft 19, satisfying the principle of equal rotational speed.

[0033] In this braking system, the acceleration output shaft 11 rotates in the same direction as the aircraft wheel hub 20, while the constant velocity output shaft 19 rotates in the opposite direction. Since the left and right wheels of the aircraft rotate in opposite directions, the self-powered hydraulic pump can be optionally installed on either the acceleration output shaft 11 or the constant velocity output shaft 19, allowing the same type of hydraulic pump (with the same direction) to be installed on both wheels, achieving standardization. Both the acceleration output shaft 11 and the constant velocity output shaft 19 have identical internal splines on their right ends, transmitting rotational speed and torque to the self-powered hydraulic pump. During this process, the rotational speed and torque of the aircraft wheels are transmitted to the self-powered hydraulic pump through the universal mechanical energy harvesting device of this invention, realizing the function of mechanically extracting and outputting energy from the aircraft wheels.

[0034] The mechanical energy harvesting device of the present invention can be applied to various aircraft and automobile tires for mechanical energy harvesting and output. According to the size of the tire space structure, the center distances a1 and a2 of the gear set are adjusted, and the number of teeth z of the two pairs of gears is adjusted according to the usage requirements, thereby achieving output at different speeds.

[0035] In this embodiment, the mechanical energy harvesting mechanism is designed within the extremely confined enclosed space of the aircraft wheel and landing gear shaft. This mechanism extracts the mechanical energy with a certain rotational speed and torque generated by the high-speed rotation of the aircraft wheel hub during landing and provides it to the hydraulic pump. The rotational speed and torque can be transmitted to the end-user hydraulic pump through the mechanical energy harvesting mechanism. The hydraulic pump converts the input mechanical energy into hydraulic energy output, which acts on the brake system actuator to achieve the braking function.

[0036] The foregoing descriptions have outlined some exemplary embodiments of the present invention. It is understood that these embodiments are merely illustrative and do not constitute a limitation on the scope of protection of the present invention. Features in these embodiments can be rearranged in suitable ways, and the resulting solutions remain within the scope of protection claimed by the present invention. All other embodiments obtained by those skilled in the art based on the foregoing embodiments without inventive effort, i.e., all modifications, equivalent substitutions, and improvements made within the spirit and principles of this application, fall within the scope of protection claimed by the present invention.

Claims

1. A universal mechanical energy harvesting device for large aircraft, characterized in that, include: The gear consists of a large acceleration gear (2), a small acceleration gear (5), a constant velocity driving gear (8), an acceleration output shaft (11), a constant velocity driven gear (15), and a constant velocity output shaft (19). The small acceleration gear (5) and the constant velocity driving gear (8) are sequentially mounted and fixed on the acceleration output shaft (11), and the constant velocity driven gear (15) is mounted and fixed on the constant velocity output shaft (19). The small acceleration gear (5) meshes internally with the large acceleration gear (2), and the constant velocity driving gear (8) meshes externally with the constant velocity driven gear (15). Multiple stepped cylindrical pins (1) penetrate the circumferential surface of the large acceleration gear (2).

2. The universal mechanical energy harvesting device for large aircraft according to claim 1, characterized in that, The acceleration output shaft (11) has two slots formed by symmetrically cutting off the upper and lower parts and the left and right parts to form a runway-shaped cross section, which are used to install the acceleration pinion (5) and the constant speed drive gear (8) respectively. The constant speed output shaft (19) has one slot formed by symmetrically cutting off the upper and lower parts to form a runway-shaped cross section, which is used to install the constant speed driven gear (15).

3. The universal mechanical energy harvesting device for large aircraft according to claim 1, characterized in that, A first limiting sleeve (7) is installed on the side of the constant speed driving gear (8) and sleeved on the acceleration output shaft (11), and a second limiting sleeve (14) is installed on the side of the constant speed driven gear (15) and sleeved on the constant speed output shaft (19).

4. A universal mechanical energy harvesting device for large aircraft according to claim 1, characterized in that, Both the acceleration output shaft (11) and the constant speed output shaft (19) are secured at one end by a self-locking nut.

5. A braking system for a large aircraft, comprising an aircraft hub (20), a landing gear axle (21), and a brake actuator (23), wherein the aircraft hub (20) is fitted onto the landing gear axle (21), and the brake actuator (23) is mounted on the side of the aircraft hub (20), characterized in that, It also includes a universal mechanical energy harvesting device (22) for a large aircraft as described in any one of claims 1-4, wherein the stepped cylindrical pin (1) is inserted into the pin hole of the aircraft hub (20), and the acceleration gear (2) is fixedly connected to the aircraft hub (20) via screws (3); a small bearing and a large bearing are respectively fitted on the acceleration output shaft (11) and the constant velocity output shaft (19), and the acceleration output shaft (11) and the constant velocity output shaft (19) are both installed and positioned in the brake actuator (23) through the small bearing and the large bearing.

6. A braking system for a large aircraft according to claim 5, characterized in that, It also includes a bearing support seat, in which the large bearing is fixed and positioned with the brake actuator (23) via the bearing support seat.

7. A braking system for a large aircraft according to claim 6, characterized in that, The two bearing support seats have parallel straight edges on adjacent sides.

8. A braking system for a large aircraft according to claim 7, characterized in that, A retaining ring (17) is installed on the outer side of the bearing support seat, and the outer diameter of the retaining ring (17) is larger than the outer diameter of the bearing support seat.

9. A braking system for a large aircraft according to claim 5, characterized in that, The small bearing on the acceleration output shaft (11) is located between the acceleration pinion (5) and the constant velocity drive gear (8), and the large bearing on the acceleration output shaft (11) is located on the other side of the constant velocity drive gear (8); the position of the small bearing on the constant velocity output shaft (19) corresponds to the position of the small bearing on the acceleration output shaft (11), and the position of the large bearing corresponds to the position of the large bearing on the acceleration output shaft (11).

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