Rotor wing tilting mechanism for end part of wing of electric tilting rotorcraft

Abstract

The invention relates to a rotor wing tilting mechanism for the ends of wings of an electric tilting rotorcraft, and aims to provide an efficient, safe and economical solution suitable for the electric tilting rotorcraft. According to the tilting mechanism, a worm and gear transmission mode is adopted, the stable tilting and self-locking functions of the rotor wing are achieved through the precise meshing design, the structural design is simplified, and an additional tilting locking device is removed. The steering engine, the worm gear, the worm, the motor and the rotor wing are directly installed on the tilting box, the tilting box is installed on the tilting mechanism connecting shaft through a bearing, and the tilting mechanism connecting shaft is connected with the wing. The steering engine directly drives the worm to rotate, the worm drives the worm gear to rotate, and the worm gear drives the tilting box and the rotor wings to tilt together. The rotor wing tilting mechanism has the advantages of being simple and reliable in structure, high in tilting operation efficiency and the like.

Description

Technical Field

[0001] The present invention relates to the field of electric vertical take-off and landing (eVTOL) aircraft, and in particular to a rotor tilt mechanism solution for a wing end of an electric tiltrotor aircraft. Background Art

[0002] Electric vertical take-off and landing (eVTOL) aircraft, combining the vertical take-off and landing capabilities of helicopters with the fast, long-range cruising capabilities of propeller aircraft, are key to developing the low-altitude economy. Electric tiltrotors, the most advanced of these eVTOL configurations, are revolutionizing urban air mobility, not only helping to reduce carbon emissions but also providing a rapid solution to peak-hour road congestion. As the technology matures and costs decrease, electric tiltrotors are expected to become a vital component of future urban transportation, contributing to the sustainable development of the low-altitude economy.

[0003] The rotor tilt mechanism is a core component of electric tiltrotors and can be installed in the middle and ends of their wings. This invention proposes a rotor tilt mechanism for the ends of electric tiltrotors. This mechanism utilizes a worm gear transmission method with a high transmission ratio to optimize the friction coefficient, thereby achieving precise control and effective self-locking of the rotor. The worm gear eliminates the need for an external locking device, significantly improving flight safety and maintenance convenience, and providing a safe and reliable technical guarantee for electric tiltrotors. Summary of the Invention

[0004] Traditional rotor tilt mechanisms utilize a four-bar linkage, which presents challenges such as complex structure and poor control accuracy. Furthermore, during flight transitions (transitional flight modes), after the tilt servo tilts the rotor to a predetermined angle, it relies on a limiter and the servo to continuously apply torque to maintain the rotor's tilt position. Although the servo has a self-locking function, this not only increases the servo's load, increases power requirements, and reduces flight range, but also reduces reliability, making it difficult to maintain stable rotor tilt positioning.

[0005] To address the shortcomings of the existing technology, this invention proposes a rotor tilt mechanism for the wing tips of electric tiltrotors. This mechanism utilizes a worm gear transmission to achieve precise rotor tilt control and effective self-locking, eliminating the need for an external locking device, simplifying the structure, and improving the reliability and ease of maintenance of the tilt mechanism.

[0006] The technical solution adopted by the present invention is: a rotor tilt mechanism for the wing end of an electric tiltrotor aircraft, characterized in that it includes a wing, a rotor, a tilt mechanism connecting shaft and a tilt box. The tilt mechanism connecting shaft connects the wing and the tilt box, and the tilt mechanism connecting shaft connects the wing end and the tilt box. The rotor is installed on the tilt box, and the tilt angle can be controlled according to different flight modes to meet the requirements of different flight modes such as vertical take-off and landing, horizontal flight and tilt transition flight. The tilt box is located below the rotor, and a worm gear transmission system is designed inside it to provide a positioning and limiting function for the precise engagement of the worm gear. The precise control of the rotor tilt angle is achieved by rotating the tilt box around the tilt mechanism connecting shaft.

[0007] Furthermore, the tilt box is mounted on the wing via a tilt mechanism connecting shaft that inserts into the wing end surface. This design avoids taking up excess space, and the entire tilt mechanism is designed as a detachable component, improving the ease of maintenance of the electric tiltrotor aircraft. The tilt mechanism connecting shaft adopts a hollow design, ensuring stability and strength while minimizing weight.

[0008] Furthermore, the tilt box is designed with thin-walled aluminum alloy material to ensure that it has sufficient strength and torsion resistance. The tilt box includes a tilt box frame, a lightening hole, a drive servo support, a worm gear assembly, a worm assembly, a seat bearing, and a servo fixing surface. The worm gear and worm assembly are meshed and driven with each other, and two seat bearings fix the worm gear shaft and the worm shaft on two parallel planes. From the perspective of the rotor direction, the worm gear shaft and the worm shaft are arranged vertically. In the reference frame of the tilt box, the rotation of the worm gear and worm assembly is limited to their respective rotation axes, so they have only one rotational degree of freedom and no displacement degree of freedom. This design ensures the motion accuracy and stability between components, improving overall work efficiency and reliability.

[0009] Furthermore, the tilt box is connected via a precision-matched bearing assembly with the worm gear and worm shaft. This design ensures efficient meshing of the worm gear and worm shaft, thereby ensuring transmission efficiency and significantly improving self-locking performance. The drive servo mount and servo mounting surface ensure the servo remains stable during operation, preventing any loosening or displacement. The servo drives the servo mount, enabling precise rotation of the worm shaft assembly, which in turn drives the tilt box through the worm gear assembly to achieve rotor tilt.

[0010] Furthermore, the worm gear shaft and worm wheel are bolted together into a single structure, ensuring reliability under rotational conditions. Both ends of the worm gear shaft are connected to the tilt box frame via worm gear coupling bearings, ensuring stable operation of the worm gear assembly during operation. The worm gear coupling bearings primarily support the worm gear assembly's rotation, significantly improving the efficiency of the entire transmission system by reducing frictional resistance. The design of the worm gear coupling bearings not only ensures precise engagement between the worm wheel and worm, but also effectively reduces energy loss due to friction and minimizes wear on mechanical components.

[0011] Furthermore, the precise design of the module of the worm assembly and worm wheel assembly ensures efficient meshing and stable transmission between the worm wheel and worm. The materials of the worm wheel and worm possess excellent wear and corrosion resistance, enabling long-term stable operation under high-load and high-speed conditions, reducing performance degradation due to wear. In particular, the optimized design of the worm wheel tooth count ensures an optimal match between the meshing angle and transmission ratio between the worm wheel and worm, achieving one-way self-locking. This efficient self-locking mechanism provides a strong guarantee for the safety and stability of the electric tiltrotor aircraft, ensuring the accuracy and reliability of the control system.

[0012] Compared with the prior art, the present invention has the following beneficial effects: (1) This mechanism uses a worm gear transmission method. Through precise meshing of the worm gear and worm, it achieves precise control of the rotor and effective self-locking function, eliminating the need for additional locking devices. Unlike traditional designs, this invention eliminates the need for external locking devices, simplifies the overall structure, makes the tilt mechanism more compact and reliable, and improves the safety and maintenance convenience of the electric tiltrotor.

[0013] (2) The tilt mechanism is not only suitable for wing end rotors, but also has high scalability. Its core components can be flexibly used in the tilt mechanism design of electric tilt rotor aircraft.

[0014] (3) The end of the tilting mechanism is designed to be detachable. This innovation not only improves the maintenance convenience of the tilting mechanism, but also provides more flexibility for future technology upgrades and component replacements. Key components can be easily replaced or upgraded according to actual needs, further reducing maintenance costs and shortening downtime. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 The figure is an assembly diagram of the rotor tilt mechanism and the wing used for the wing end of an electric tiltrotor aircraft; Figure 2 A three-dimensional structural diagram of a rotor tilt mechanism for an electric tiltrotor aircraft wing end; Figure 3A top view of a rotor tilt mechanism for an electric tiltrotor aircraft wing end; Figure 4 It is a partial schematic diagram of the worm gear assembly in the rotor tilt mechanism; Figure 5 It is a partial schematic diagram of the tilt box in the rotor tilt mechanism; The numbers in the figure are: 1. Wing, 2. Rotor, 3. Tilt mechanism connecting shaft, 4. Tilt box, 41. Servo fixing surface, 42. Motor mounting surface, 43. Lightening hole, 44. Drive servo support, 45. Worm gear assembly, 452. Worm gear shaft, 451. Worm gear, 46. Worm assembly, 461. Worm shaft, 462. Worm, 47. Connecting bearing, 471. Worm connecting bearing, 472. Worm gear connecting bearing DETAILED DESCRIPTION

[0016] In order to further understand the features, technical means, specific objectives and functions achieved by the present invention, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0017] Reference Figures 1 to 5 As shown, the present embodiment is a rotor tilt mechanism for the wing end of an electric tiltrotor aircraft, comprising a wing 1, a rotor 2, a tilt mechanism connecting shaft 3 and a tilt box 4. It is characterized in that the tilt mechanism connecting shaft 3 is located between the wing 1 and the rotor 2, connecting the end of the wing 1 and the tilt box 4, and its main function is to support the tilt box 5. The rotor 2 is connected to the motor, which is fixedly mounted on the tilt box 4. The tilt box 4 rotates around the tilt mechanism connecting shaft 3 to achieve precise tilt control of the rotor 2. The tilt box 4 of this embodiment significantly reduces the overall weight while ensuring structural strength through the design of the lightening hole. The precise meshing of the worm wheel 452 and the worm 462 not only ensures efficient transmission, but also realizes a self-locking function, avoiding the need for additional locking devices in traditional tilt mechanisms.

[0018] Reference Figures 2 to 5 As shown, the tilt box 4 is connected to the wing 1 via the tilt mechanism connecting shaft 3, ensuring a secure connection between the rotor 2 and the tilt box as a whole and the wing 1. The coupling bearing 47 limits the worm wheel assembly 45 and the worm assembly 46, ensuring precise engagement between the worm wheel 451 and the worm 462. The rotational characteristics of the coupling bearing 47 ensure that the worm wheel 451 and the worm 462 can rotate freely in their respective axial directions. In this way, the worm wheel 451 and the worm 462 can maintain an optimal meshing state during operation, allowing the tilt mechanism to operate stably and efficiently. The driving servo support 44 further realizes the rotation of the servo-driven tilt box 4 around the tilt mechanism connecting shaft 3 by driving the servo on the servo fixing surface 41, thereby driving the rotor 2 to tilt.

[0019] Reference Figure 4As shown, the optimized module configuration of the worm gear and worm achieves a good balance between self-locking function and transmission efficiency. The driving servo support 44 is connected to the servo drive plate, and the servo is fixed to the servo mounting surface 41. The servo drives the servo support 44, causing the worm assembly 46 to rotate. The worm gear 451 precisely meshes with the worm gear 462, driving the worm gear assembly 45 to rotate. Because the worm gear assembly 45 is fixedly connected to the tilt box 4, the rotation of the worm gear ultimately drives the tilt box 4, thereby tilting the rotor 2.

[0020] Reference Figure 5 As shown, the tilt box 4 has a perforated design that reduces weight, maximizing weight reduction while ensuring strength and rigidity.

[0021] Working principle: Refer to Figures 1 to 5 As shown, when the tilt angle of rotor 2 needs to be adjusted, the automatic controller operates the servo. The servo is fixed to the servo mounting surface 41 and drives the servo support 44 to rotate, which in turn drives the worm assembly 46. Due to the positioning constraints of the worm gear 451 and worm 462 by the coupling bearing 47, the tilt mechanism connecting shaft 3 and the worm gear 451 remain relatively stationary. The relative rotation between the worm gear 451 and the worm 462 is reflected as rotation between the tilt mechanism connecting shaft 3 and the tilt box 4. When the worm assembly 46 rotates, the worm gear assembly 45 is connected to the tilt box 4 via the worm gear 451, thereby driving the rotor 2 to tilt about the tilt mechanism connecting shaft 3, completing the adjustment of the rotor tilt angle. When rotor 2 reaches the desired tilt angle, the servo stops, and the rotor stops tilting. During this process, the self-locking function of the worm gear assembly comes into play, locking the one-way transmission from the worm gear to the worm, preventing the rotor from tilting. In the self-locking state, the worm gear cannot drive the worm, and the rotor maintains a fixed angle. When the rotor tilt angle needs to be changed, the servo is activated again, driving the tilt of rotor 2, achieving smooth switching between different flight modes.

[0022] The above embodiment merely represents one embodiment of the present invention, and while the description is relatively specific and detailed, it should not be construed as limiting the scope of the present invention. It should be noted that a person skilled in the art may make various modifications and improvements without departing from the spirit of the present invention, and these modifications and improvements fall within the scope of protection of the present invention. Therefore, the scope of protection of the present invention shall be determined by the appended claims.

Claims

1. A rotor tilt mechanism for a wing end of an electric tilt rotor aircraft, characterized in that: The invention comprises a wing (1), a rotor (2), a tilt mechanism connecting shaft (3) and a tilt box (4). The wing (1) can generate lift during forward flight, and its end is connected to the tilt box (4) via the tilt mechanism connecting shaft (3). The rotor (2) is mounted on the tilt box (4) and can change the tilt angle according to different flight modes such as vertical take-off and landing, horizontal flight and tilt transition flight to generate pulling force for vertical take-off and landing or horizontal forward flight. The tilt box (4) is mounted with a steering gear, a motor, a rotor, a worm gear and a worm rotating component. The tilt box (4) rotates around the tilt mechanism connecting shaft (3) to realize the tilting of the rotor (2) to realize different flight modes. The design of the tilt mechanism not only enhances the performance of the electric tilt rotor aircraft during vertical take-off and landing, tilt transition flight and forward flight, but also provides higher operational safety and flight efficiency.

2. A rotor tilt mechanism for a wing end of an electric tilt rotor aircraft according to claim 1, characterized in that: The tilt mechanism connecting shaft (3) is hollow inside, one end of which is connected to the end of the wing (1), and the other end of which is connected to the worm gear shaft (452), so that a portion of the torque of the rotor and wing can be unloaded during the tilting process, which is conducive to stable flight.

3. The rotor tilt mechanism for the wing end of an electric tilt rotor aircraft according to claim 1, characterized in that: The tilt box (4) includes a steering gear mounting surface (41), a motor mounting surface (42), a lightening hole (43), a driving steering gear support (44), and a worm gear assembly (45), a worm assembly (46) and a seat bearing (47). The steering gear fixing surface (41) is used to install the steering gear, so that the steering gear drive plate and the driving steering gear support (44) are tightly connected by bolts, so that the steering gear and the tilt box (4) become a whole. The motor mounting surface (42) is connected to the motor, and the motor is connected to the rotor, so that the rotor and the motor and the tilt box (4) become a whole. Therefore, the rotation of the steering gear can make the tilt box (4) and the rotor (2) rotate together around the tilt mechanism connection shaft (3), thereby realizing the tilting of the rotor (2).

4. The rotor tilt mechanism for the wing end of an electric tilt rotor aircraft according to claim 3, characterized in that: The tilt box (4) has only one relative rotational freedom between itself and the tilt mechanism connecting shaft (3) through the worm wheel bearing (472), the worm wheel shaft (452), the worm bearing (471) and the worm shaft (461). The built-in worm wheel (452) and the worm (462) are effectively meshed by the radial positioning of the worm bearing (471) and the worm wheel bearing (472).

5. The rotor tilt mechanism for the wing end of an electric tilt rotor aircraft according to claim 4, characterized in that: The worm gear assembly (45) comprises a worm gear shaft (452) and a worm gear (451), which are connected as a whole by bolts, and both ends are connected to the worm gear seat bearing (472) and fixed on the tilt box (4), and its rotation function is realized by the worm gear seat bearing (472). The end of the worm gear shaft (452) close to the wing (2) is the tilt mechanism connecting shaft (3).

6. A rotor tilt mechanism for a wing end of an electric tilt rotor aircraft according to claim 5, characterized in that: The worm assembly (46) comprises a worm (462) and a worm shaft (461), which are connected as a whole by bolts, and the end close to the wing is connected to the worm seat bearing (471) and fixed on the tilt box (4), and the end away from the wing is connected to the steering gear drive plate, and the steering gear is installed on the steering gear fixing surface (41). The worm shaft (461) is connected to the tilt box (4) as a whole.

7. The rotor tilt mechanism for the wing end of an electric tilt rotor aircraft according to claim 3, characterized in that: The driving steering gear support (44) is connected to the steering gear driving plate, and the steering gear is installed on the steering gear fixing surface (41). The steering gear drives the steering gear support (44), drives the worm assembly (46) to rotate, and the effective meshing of the worm wheel (451) and the worm (462) causes the worm wheel assembly (45) to rotate. Since the worm wheel assembly (45) is fixedly connected to the tilt box (4), the worm wheel assembly (45) drives the tilt box (4) to rotate, thereby driving the rotor (2) to tilt.

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