Electric helicopter rotor tilting mechanism

Abstract

The invention belongs to the field of helicopter tilting mechanisms, and relates to an electric helicopter rotor tilting mechanism. Comprising a motor support (1), a tilting rocker arm (2), a tilting rotating shaft assembly (7), a universal ring assembly (8) and a lead screw speed reduction structure (5), the lead screw speed reduction structure (5) comprises a tilting motor (6), a primary gear reducer and a lead screw (4), and the lead screw speed reduction structure (5) is connected with a machine body structure (3) through the universal joint assembly (8); the output end of the tilting motor (6) is connected with the input end of the primary gear reducer; the output end of the primary gear reducer is connected with one end of a lead screw (4); a rotor wing driving motor and a rotor wing are mounted on the motor support (1); one end of the tilting rocker arm (2) is fixedly connected with the motor support (1) through a bolt; the other end of the tilting rocker arm (2) is connected with the other end of the lead screw (4) through a joint bearing (17); and the motor support (1) is hinged with the machine body structure (3) through a tilting rotating shaft assembly (7).

Description

Technical Field

[0001] The invention belongs to the technical field of design of electric-driven helicopter tilting mechanisms, and in particular relates to an electric helicopter rotor tilting mechanism. Background Art

[0002] Electric vertical take-off and landing aircraft have multiple flight modes, including rotor flight mode, transition mode and fixed-wing flight mode, and can convert between modes in the air to improve the flight efficiency of the aircraft. Therefore, tilt-rotor aircraft need to design a tilt actuator mechanism to drive the rotor to rotate to achieve flight mode conversion. Summary of the invention

[0003] Purpose of the invention: To provide an electric helicopter rotor tilting mechanism, which realizes the tilting of the rotor between fixed-wing and helicopter modes.

[0004] Technical solution:

[0005] An electric helicopter rotor tilt mechanism comprises: a motor support 1, a tilt rocker arm 2, a tilt shaft assembly 7, a universal ring assembly 8 and a lead screw reduction structure 5.

[0006] Among them, the screw reduction structure 5 includes a tilt motor 6, a first-stage gear reducer, and a screw 4. The screw reduction structure 5 is connected to the fuselage structure 3 through a universal joint assembly 8; the output end of the tilt motor 6 is connected to the input end of the first-stage gear reducer; the output end of the first-stage gear reducer is connected to one end of the screw 4; the rotor drive motor and the rotor are installed on the motor support 1; one end of the tilt rocker arm 2 is fixed to the motor support 1 by bolts; the other end of the tilt rocker arm 2 is connected to the other end of the screw 4 by a joint bearing 17; the motor support 1 and the fuselage structure 3 are hinged through the tilt shaft assembly 7.

[0007] Furthermore, the lead screw 4 is a two-force rod structure to prevent jamming due to deformation.

[0008] Furthermore, the universal ring assembly 8 includes: a flange 14, a universal joint ring 15 and a second shaft pin 16. The universal ring assembly 8 is a cross universal joint. The outer ring of the universal ring assembly 8 is fixedly connected to the body structure 3 through the flange 14, and the inner ring of the universal ring assembly 8 is structurally connected to the screw reducer 5.

[0009] Furthermore, the tilt axis assembly 7 includes: a first pin shaft 9, a double-row tapered roller bearing 10, a first bushing 11 and a second bushing 12, and a nut 13, wherein the mounting leg of the motor support 1 adopts two double-ear structures, and the fuselage structure 3 adopts two single-ear structures, and both single-ear structures are provided with mirror-arranged ribs, and each single ear can transmit axial loads in a single direction. A pair of double-row tapered roller bearings 10 is installed in the middle of the first pin shaft 9, and the inner ring of the double-row tapered roller bearing 10 is axially positioned by the first bushing 11 and the second bushing 12, and the double-row tapered roller bearing 10 is fixed by pressing the first bushing 11 and the second bushing 12 by the nut 13, and the outer ring of the double-row tapered roller bearing 10 is connected to the fuselage structure 3 and one side is against the rib.

[0010] Furthermore, there are two tilting shaft assemblies 7 which are symmetrically distributed, and the two tilting shaft assemblies 7 together can transmit various axial and tilting working loads.

[0011] Furthermore, the flange 14 is connected to the fuselage structure 3 via four connecting bolts 17 to transmit the axial load.

[0012] Furthermore, there are four evenly distributed connecting holes on the universal joint ring 15, two of which are connected to the screw reduction structure 5 through the second pin shaft 16. The universal joint ring 15 and the screw reduction structure 5 can swing around the axes of the two second pin shafts 16, and the remaining two connecting holes and the flange 14 are connected through another two second pin shafts 16, providing swing in another direction to compensate for structural deformation and installation errors, thereby greatly reducing the risk of screw jamming.

[0013] Furthermore, the first-stage gear reducer is mainly composed of an input gear 20, an output gear 21, an input bearing 23, an output bearing 22, a casing 24, a bushing 27 and a seal 25, wherein:

[0014] The input gear 20 is meshed with the output gear 21; there are two input bearings 23 and they are used to support the two ends of the input gear 20; the output gear 21 is spline-connected with the lead screw nut; there are two output bearings 22 and they are used to support the lead screw nut; a bushing 27 is provided between the output bearing 22 and the casing 24; seals 25 are provided at the input end of the input gear 20 and at both ends of the lead screw nut.

[0015] Beneficial effects:

[0016] The electric helicopter rotor tilting mechanism of the present invention realizes the tilting of the rotor between the fixed-wing mode and the helicopter mode, has a simple structure, is light in weight, and is safe and reliable. The present invention is suitable for the tilting of the electric helicopter rotor. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a front view of the electric helicopter rotor tilting mechanism according to an embodiment of the present invention;

[0018] Figure 2 A top view of the electric helicopter rotor tilting mechanism according to an embodiment of the present invention;

[0019] Figure 3 is a cross-sectional view of a tilt shaft assembly;

[0020] Figure 4 It is a structural diagram of the universal joint ring assembly;

[0021] Figure 5 It is a cross-sectional view of the screw speed reduction structure;

[0022] Among them, the motor support 1, the tilt rocker arm 2, the fuselage structure 3, the screw 4, the screw reduction structure 5, the tilt motor 6, the tilt shaft assembly 7, the universal ring assembly 8, the first pin 9, the double-row tapered roller bearing 10, the first bushing 11 and the second bushing 12, the nut 13, the flange 14, the universal joint ring 15, the second pin 16, the spherical bearing 17, the first bolt 18, the second bolt 19, the input gear 20, the output gear 21, the output bearing 22, the input bearing 23, the casing 24, the seal 25, the bolt connector 26, and the bushing 27. DETAILED DESCRIPTION

[0023] The aircraft to which the electric helicopter rotor tilt mechanism of the present invention belongs consists of four tiltable front rotors and four non-tiltable rear rotors. The four tiltable front rotors are driven by four sets of tilt mechanisms. The tilt actuation systems of the four front rotors have the same structure, and are mainly composed of a tilt drive motor, a gear transmission mechanism, a ball screw, etc. The tilt controller receives the instruction of the tilt actuation system to control the tilt motor. The tilt motor drives the gear transmission mechanism and the ball screw to convert the motor rotational motion into linear motion, driving the rotor motor and the rotor to rotate, thereby realizing the mutual conversion of the three modes of helicopter, tilt transition and turboprop aircraft.

[0024] The electric helicopter rotor tilting mechanism of the present invention realizes the tilting of the rotor between the fixed-wing mode and the helicopter mode, has a simple structure, is light in weight, and is safe and reliable. The present invention is suitable for the tilting of the electric helicopter rotor.

[0025] like Figure 1-5 , an electric helicopter rotor tilt mechanism, mainly comprising a motor support 1, a tilt rocker arm 2, a tilt shaft assembly 7, a universal ring assembly 8 and a screw reducer structure 5. The motor support 1 is equipped with a rotor drive motor and a rotor, which can rotate around the shaft structure 7 to achieve the tilt of the rotor. The universal ring assembly 8 is composed of a flange 14, a universal joint ring 15 and a second shaft pin 16, and is a cross universal joint. The outer ring of the universal ring assembly 8 is fixedly connected to the body structure 3 through the flange 14, and the inner ring of the universal ring assembly 8 is structurally connected to the screw reducer 5.

[0026] The motor support 1 is fixedly connected to the tilting rocker arm 2 by a first bolt 18 and a second bolt 19, and the lead screw 4 is connected to the tilting rocker arm 2 by a spherical bearing 17. The lead screw is a two-force rod structure to prevent jamming caused by deformation.

[0027] Taking the transition from a multi-rotor to a fixed-wing mode as an example, during the tilting process, the tilt motor 6 drives the screw reducer 5 to rotate. The screw reducer 5 is connected to the fuselage structure 3 through the universal ring assembly 8. The tilt mechanism can rotate in the pitch plane. The tilt motor 6 drives the screw 4 to move backward, driving the motor support 1 to rotate around the tilt shaft assembly 7. The rotor axis gradually transitions to the horizontal and changes to the fixed-wing mode.

[0028] The low-friction, high-load tilt shaft assembly 7 installs the motor support 1 on the fuselage structure 3 and realizes the rotation of the rotor around the tilt shaft assembly 7. The mounting legs of the motor support 1 adopt two double-ear structures, and the fuselage structure 3 adopts two single-ear structures. Both single-ear structures are provided with mirror-arranged retaining edge structures, and each single ear can transmit axial loads in a single direction. The ear of the motor support 1 and the fuselage structure 3 are connected through two coaxial tilt shaft assemblies 7. A pair of double-row tapered roller bearings 10 are installed in the middle of the first pin shaft 9. The inner ring of the double-row tapered roller bearing 10 is axially positioned by the first bushing 11 and the second bushing 12. The double-row tapered roller bearing 10 is fixed by pressing the first bushing 11 and the second bushing 12 through the nut 13. The outer ring of the double-row tapered roller bearing 10 is connected to the fuselage structure 3 and one side is against the retaining edge. The two tilt shaft assemblies 7 can transmit various axial and tilting working loads together, and the disassembly and adjustment of the tilt shaft assembly 7 are convenient.

[0029] Universal ring assembly 8 Figure 3 As shown, the main function of the universal ring assembly 8 is: when the tilt mechanism performs a tilting action, the movement of the lead screw 4 has a certain swing, the axis of the lead screw 4 does not maintain a straight line, and there is a certain angle change. At this time, in order to ensure the continuity of the tilting action, a universal joint assembly 8 is required to transmit the swing of the lead screw 4; by connecting the universal ring assembly 8 with the lead screw reduction structure 5, it is ensured that the lead screw reduction structure 5 can rotate around the second pin shaft 16 to a certain extent, thereby providing the required swing for the ball screw during the tilting process. The flange 14 is connected to the fuselage structure 3 through four connecting bolts 17 to transmit the axial load. There are 4 evenly distributed connecting holes on the universal joint ring 15, two of which are connected to the lead screw reduction structure 5 through the second pin shaft 16. The universal joint ring 15 and the lead screw reduction structure 5 can swing around the two second pin shafts 16 axes. The remaining two connecting holes and the flange 14 are connected through the other two second pin shafts 16 to provide another direction of swing, which is used to compensate for structural deformation and installation errors, greatly reducing the risk of lead screw jamming.

[0030] Screw reduction structure 5 Figure 4As shown, the screw reduction structure 5 mainly includes a tilt motor 6, a first-stage gear reducer, and a screw 4. The tilt actuation reducer 5 is connected to the body mechanism 3 through a universal joint assembly 8 to realize the swinging motion of the screw 4, and at the same time transmit the rotor load received by the screw 4 to the body structure 3. One side of the screw reduction structure 5 is connected to the motor support 1 through a joint bearing 17, and the other side of the screw reduction structure 5 is connected to the fuselage structure 3 through a universal joint assembly 8. The reducer assembly 5 cannot transmit the various torques transmitted by the front rotor assembly, but can only transmit the axial force of the screw 4, ensuring that the screw is a two-force rod. The various torques received by the front rotor assembly are transmitted to the fuselage structure 3 through the tilt shaft assembly 7.

[0031] The first-stage gear reducer is mainly composed of an input gear 20, an output gear 21, an input bearing 23, an output bearing 22, a casing 24, a bushing 27, a bolt connector 26, and a seal 25. On the one hand, the reducer screw structure 5 can transmit the driving speed of the motor 6 to the screw 4 through the input gear 20 and the output gear 21, converting the rotary motion into linear motion to complete the tilting action. On the other hand, the reducer screw structure 5, as the main force transmission structure, can transmit the load transmitted by the rotor to the screw 4 through a pair of output bearings 22 arranged in the first-stage gear reducer to the universal joint assembly 8, and then transmit the load to the body structure 3, so as to prevent the ball screw from being loaded and causing structural damage.

[0032] The key points of the present invention are:

[0033] The structure of the present invention has an overall light weight, a simple structure, and is easy to install and adjust; the tilt shaft assembly 7 has a small radial dimension and a strong deformation resistance, and is composed of two sets of tapered roller bearing assemblies, which can simultaneously withstand large radial and bidirectional axial loads; the universal ring assembly 8 can adjust the installation deformation error of the screw assembly, and is used for deformation coordination and error adjustment when the screw swings, thereby realizing the transmission of additional bending moment to the screw structure; the screw reduction structure 5, a small gear driven by a motor, the small gear drives the large gear, and the large gear drives the ball screw nut to rotate, and a pair of bearings that can transmit loads in both directions are installed on the outer ring of the nut, which are used to transmit the load of the nut to the casing structure.

Claims

1. An electric helicopter rotor tilt mechanism, characterized in that: include: A motor support (1), a tilt rocker arm (2), a tilt shaft assembly (7), a universal ring assembly (8) and a lead screw speed reduction structure (5), The lead screw reduction structure (5) comprises a tilt motor (6), a first-stage gear reducer, and a lead screw (4); the lead screw reduction structure (5) is connected to the fuselage structure (3) via a universal joint assembly (8); the output end of the tilt motor (6) is connected to the input end of the first-stage gear reducer; the output end of the first-stage gear reducer is connected to one end of the lead screw (4); a rotor drive motor and a rotor are mounted on the motor support (1); one end of the tilt rocker arm (2) is fixedly connected to the motor support (1) via bolts; the other end of the tilt rocker arm (2) is connected to the other end of the lead screw (4) via a joint bearing (17); and the motor support (1) is hinged to the fuselage structure (3) via a tilt shaft assembly (7).

2. The electric helicopter rotor tilting mechanism according to claim 1, characterized in that: The lead screw (4) is a two-force rod structure to prevent jamming due to deformation.

3. The electric helicopter rotor tilting mechanism according to claim 1, characterized in that: The universal ring assembly (8) comprises: a flange (14), a universal joint ring (15) and a second shaft pin (16). The universal ring assembly (8) is a cross universal joint. The outer ring of the universal ring assembly (8) is fixedly connected to the machine body structure (3) through the flange (14), and the inner ring of the universal ring assembly (8) is structurally connected to the screw reducer (5).

4. The electric helicopter rotor tilting mechanism according to claim 1, characterized in that: The tilt shaft assembly (7) comprises: a first pin shaft (9), a double-row tapered roller bearing (10), a first bushing (11) and a second bushing (12), and a nut (13), wherein the motor support (1) mounting leg adopts two double-ear structures, and the fuselage structure (3) adopts two single-ear structures, and both single-ear structures are provided with mirror-image-arranged flanges, and each single ear can transmit an axial load in a single direction. A pair of double-row tapered roller bearings (10) is installed in the middle of the first pin shaft (9), and the inner ring of the double-row tapered roller bearing (10) is axially positioned by the first bushing (11) and the second bushing (12), and the double-row tapered roller bearing (10) is fixed by pressing the first bushing (11) and the second bushing (12) by the nut 13, and the outer ring of the double-row tapered roller bearing (10) is connected to the fuselage structure (3) and one side is against the flange.

5. The electric helicopter rotor tilting mechanism according to claim 1, characterized in that: There are two tilting shaft assemblies (7) which are symmetrically distributed. The two tilting shaft assemblies (7) together can transmit various axial and tilting loads.

6. The electric helicopter rotor tilting mechanism according to claim 3, characterized in that: The flange (14) is connected to the fuselage structure (3) via four connecting bolts (17) to transmit axial load.

7. The electric helicopter rotor tilting mechanism according to claim 3, characterized in that: There are four evenly distributed connection holes on the universal joint ring (15), two of which are connected to the screw reduction structure (5) through the second pin shaft (16). The universal joint ring (15) and the screw reduction structure (5) can swing around the axes of the two second pin shafts (16). The remaining two connection holes and the flange (14) are connected through another two second pin shafts (16) to provide swing in another direction, which is used to compensate for structural deformation and installation errors, thereby greatly reducing the risk of the screw being stuck.

8. The electric helicopter rotor tilting mechanism according to claim 1, characterized in that: The first-stage gear reducer mainly comprises an input gear (20), an output gear (21), an input bearing (23), an output bearing (22), a casing (24), a bushing (27) and a seal (25), wherein: The input gear (20) is meshed with the output gear (21); there are two input bearings (23) for supporting the two ends of the input gear (20); the output gear (21) is spline-connected with the lead screw nut; there are two output bearings (22) for supporting the lead screw nut; a bushing (27) is provided between the output bearing (22) and the casing (24); and sealing elements (25) are provided at the input end of the input gear (20) and at both ends of the lead screw nut.

Images