Annular propeller with variable pitch and cross-domain aircraft

Abstract

The invention provides a variable-pitch annular propeller and a cross-domain aircraft, and belongs to the field of cross-domain aircrafts, two connecting parts are arranged on the peripheral surfaces of an annular propeller blade and a propeller hub, the two connecting parts are arranged front and back in the axial direction of the propeller hub and are respectively set as a front blade root and a rear blade root, and the annular propeller blade is made of an elastic material and can be distorted and deformed; the movable base is connected with the rear blade root and drives the rear blade root to synchronously rotate axially relative to the propeller hub in the radial direction of the propeller hub, the annular propeller blades are twisted and deformed, and the screw pitches of the annular propeller blades are changed. The roots of the front blade and the rear blade of the annular propeller can rotate relative to the propeller hub to drive the annular propeller to elastically twist and deform and change the pitch angle of the annular propeller, so that the aircraft can automatically adjust the pitch of the annular propeller according to a medium where the aircraft is located, the propelling efficiency and the acoustic performance of the annular propeller in different media are improved, and the service life of the aircraft is prolonged. And the special flaky vortex wake of the annular propeller is weakened.

Description

Technical Field

[0001] This invention relates to the field of trans-domain vehicle technology, and more particularly to a variable pitch annular propeller and a trans-domain vehicle. Background Art

[0002] Traditional propeller designs are typically optimized for a single medium; for example, underwater propellers and aircraft propellers differ significantly in structure and performance. However, with the development of trans-domain vehicles (such as underwater aircraft and amphibious vehicles), higher demands are placed on propulsion devices. These devices need to achieve good propulsion efficiency in both air and water, and be able to flexibly adjust to environmental changes in different media. Traditional propulsion devices usually employ a fixed pitch design, which cannot achieve efficient propulsion in different media and is prone to generating significant noise and vibration during media switching. Chinese patent CN107035567B discloses a pitch range for variable pitch fans. By changing the angle between the blade and the plane of rotation, the single blade of the propeller has a variable pitch function, adapting to various application scenarios.

[0003] Annular propellers, through their unique blade structure, can reduce tip vortices and hub vortices, thereby improving propulsion efficiency and reducing noise. They have already been applied in the shipbuilding and aviation industries and represent a promising direction for cross-medium propulsion technology development. Currently, annular propellers typically have two blade roots, as the blades of an annular propeller can be considered as two single blades connected at the tip. In one type of annular propeller, the two blade roots are arranged axially along the hub. For different speed conditions and environmental media, the orientation or design parameters of the annular blades determine the propeller's blade-shaped vortex wake. Therefore, it is necessary to develop an annular propeller propulsion technology that can adapt to various media environments and has variable pitch capabilities, enabling the annular propeller to optimize its blade-shaped vortex wake according to design requirements. Summary of the Invention

[0004] In view of this, the present invention proposes a variable pitch annular propeller and a trans-domain vehicle to solve the problem that current annular propellers cannot optimize the propeller blade vortex wake according to design requirements.

[0005] The technical solution of this invention is implemented as follows: This invention provides a variable pitch annular propeller, including a hub that rotates along its axial direction; at least two annular blades arranged axially around the hub on the outer circumferential surface of the hub; at least two movable bases embedded in the outer circumferential surface of the hub; wherein, the annular blades and the outer circumferential surface of the hub have two connection points, the two connection points are arranged front and rear along the hub axial direction and are respectively designated as the front blade root and the rear blade root, the annular blades are made of elastic material and can be twisted and deformed; the movable bases are connected to the rear blade root, and the movable bases drive the rear blade root to rotate synchronously with the hub along the radial direction of the hub, causing the annular blades to twist and deform and change the pitch of the annular blades.

[0006] Based on the above technical solutions, preferably, the movable bases are arranged in pairs, with the two movable bases in each pair arranged back and forth along the rotor hub axis, and the two movable bases in each pair are connected to the front blade root and the rear blade root respectively.

[0007] Even more preferably, the rotation direction of the anterior leaf root and the posterior leaf root is the same.

[0008] More preferably, the rotation angle of the posterior leaf root is not less than the rotation angle of the anterior leaf root.

[0009] Based on the above technical solutions, preferably, the propeller hub includes a housing, which is a hollow cylinder; a fixed ring, which is fitted inside the housing; and a rotating ring, which is coaxially fitted inside the fixed ring and rotates relative to the fixed ring axis. One end of the movable base extends outward through the housing, and a rear blade root is provided on the outer end of the movable base. The other end of the movable base penetrates the inner wall of the fixed ring and approaches the outer wall of the rotating ring. A sliding pin is eccentrically provided on the end face of the movable base facing the rotating ring. A sliding groove is provided on the outer wall of the rotating ring, and the extension direction of the groove is inclined relative to the axial direction of the rotating ring. A sliding pin is inserted into the groove.

[0010] More preferably, it also includes a telescopic drive mechanism disposed on the side of the fixed ring; a spur rack connected to the telescopic drive mechanism and moving along the tangential direction of the moving ring under the drive of the telescopic drive mechanism; and an arc rack disposed on the side of the moving ring and cooperating with the spur rack.

[0011] In a further preferred embodiment, the two ends of the rear blade root are a guide edge and a follower edge, respectively, and the slide groove extends from the guide edge toward the follower edge along the rotation direction of the moving ring. In the initial state, the sliding pin is located at the end of the slide groove facing the follower edge.

[0012] More preferably, the groove is a straight groove or an arc groove; when the groove is an arc groove, its arc protrudes along the rotation direction of the moving ring.

[0013] Based on the above technical solutions, preferably, the connecting surface between the movable base and the annular blade is provided with a slot, and the movable base is detachably connected to the front blade root or the rear blade root through the slot.

[0014] On the other hand, the present invention also provides a trans-domain vehicle employing the aforementioned variable pitch annular propeller.

[0015] The variable pitch annular propeller and transoceanic vehicle of the present invention have the following advantages over the prior art: (1) The present invention enables the root of the front and rear blades of the annular propeller to rotate relative to the hub, thereby driving the annular blades to undergo elastic torsional deformation and changing the pitch angle of the annular blades. This allows the aircraft to automatically adjust the pitch of the annular propeller according to the medium in which it is located, thereby improving the propulsion efficiency and acoustic performance of the annular propeller in different media, thus improving the flexibility and adaptability of navigation, and weakening the unique sheet-like vortex wake of the annular propeller, thereby achieving the purpose of further improving propulsion efficiency and reducing noise.

[0016] (2) The present invention achieves the purpose of adjusting the blade pitch by simultaneously driving the synchronous rotation of the blade roots of each blade through the relative rotation of the inner and outer fixed ring and the movement of the straight rack and the arc rack. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 This is a top view of the annular propeller of the present invention; Figure 2 This is a perspective view of the fixed ring of the present invention; Figure 3 This is a radial cross-sectional view of the propeller hub of the present invention; Figure 4 For the present invention Figure 3 Enlarged view of point A in the middle; Figure 5 This is an axial cross-sectional view of the propeller hub of the present invention; Figure 6 For the present invention Figure 5 Enlarged view of point B in the middle; Figure 7 This is a schematic diagram of the variable pitch principle of the leaf root of the present invention; Figure 8 This is a schematic diagram illustrating the variable pitch principle of the annular propeller of the present invention. Figure 9 This is a schematic diagram illustrating the variable pitch principle of another embodiment of the leaf root of the present invention.

[0019] In the diagram: 1. Hub; 11. Housing; 12. Fixed ring; 13. Moving ring; 101. Slide groove; 2. Annular blade; 21. Front blade root; 22. Rear blade root; 3. Movable base; 31. Slide pin; 301. Slot; 4. Telescopic drive mechanism; 5. Straight rack; 6. Arc rack. DETAILED DESCRIPTION

[0020] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0021] like Figure 1 As shown, combined with Figure 2 , Figure 3 and Figure 5 The present invention provides a variable pitch annular propeller, comprising a hub 1, an annular blade 2, and a movable base 3.

[0022] The rotor hub 1 rotates along its axial direction. The rotor hub 1 is mounted on the drive shaft of the aircraft. Driven by the drive shaft, the rotor hub 1 and the annular blades 2 mounted on it rotate. The medium in which the aircraft is located flows from the front to the rear of the aircraft along the axial direction of the rotor hub 1, thereby generating propulsion.

[0023] At least two annular blades 2 are arranged axially around the outer surface of the hub 1. The annular blades 2 and the outer surface of the hub 1 have two connection points, which are arranged longitudinally along the axial direction of the hub 1 and respectively designated as the front blade root 21 and the rear blade root 22. The annular blades 2 are made of an elastic material and are capable of torsional deformation. The annular propeller of this embodiment is mainly used in cross-domain unmanned aerial vehicles. The annular blades 2 can be made of elastic plastic material or elastic polymer material. Therefore, when any blade root of the annular blade 2 rotates under the drive of the movable base 3, the main body of the annular blade 2 can undergo elastic torsional deformation without breaking or being damaged.

[0024] At least two movable bases 3 are embedded in the outer circumferential surface of the propeller hub 1; the movable bases 3 are connected to the rear blade root 22, and the movable bases 3 drive the rear blade root 22 to rotate synchronously along the radial direction of the propeller hub 1 relative to the propeller hub 1, causing the annular blade 2 to twist and deform and change the pitch of the annular blade 2. When any blade root of the annular blade 2 rotates under the drive of the movable base 3, the vehicle adjusts the orientation of the leading edge and trailing edge of the annular blade 2 according to different travel speeds, thereby weakening the unique sheet-like vortex wake of the annular propeller (especially when the rotation occurs from the trailing blade root 22 near the trailing edge, it will affect the sheet-like vortex wake), in order to improve propulsion efficiency and reduce noise. At the same time, the rotation of the blade root of the annular blade 2 changes the pitch angle of the annular blade, enabling the vehicle to automatically adjust the pitch angle of the annular blade 2 according to the medium it is in (the pitch angle refers to the degree of inclination of the blade at a certain rotation radius, and the pitch angle is different at different rotation radii), so that the pitch of the helix generated by the rotation of the annular propeller changes, improving the propulsion efficiency and acoustic performance of the annular propeller in different media, and thus improving the flexibility and adaptability of navigation.

[0025] exist Figure 5 In a preferred embodiment shown, the movable bases 3 are arranged in pairs, with the two movable bases 3 in each pair arranged back and forth along the axial direction of the hub 1. The two movable bases 3 in each pair are respectively connected to the front blade root 21 and the rear blade root 22. Since the front blade root 21 and the rear blade root 22 are arranged back and forth on the hub 1, the front blade root 21 and the rear blade root 22 need to be driven to rotate by different moving rings 13. Therefore, two sets of fixed rings 12 and moving rings 13 are arranged back and forth in the housing 11. Thus, the front blade root 21 or the rear blade root 22 of each annular blade 2 can be controlled to deflect synchronously, thereby improving the unique sheet-like vortex wake of the annular propeller.

[0026] exist Figure 8 In a preferred embodiment shown, the front blade root 21 and the rear blade root 22 rotate in the same direction. By simultaneously changing the orientation of the front blade root 21 and the rear blade root 22, the inflow and outflow conditions of the medium in which the vehicle is located can be adjusted, thereby improving the propeller's propulsion efficiency and acoustic performance.

[0027] exist Figure 8 In a preferred embodiment shown, the rotation angle of the rear blade root 22 is not less than the rotation angle of the front blade root 21. The larger rotation angle of the rear blade root 22 can cover the pitch variation requirements of improving the sheet-like vortex wake of the annular propeller at different speeds of the aircraft.

[0028] exist Figure 4 In a preferred embodiment shown, the rotor hub 1 includes a housing 11, a fixed ring 12, and a moving ring 13.

[0029] The shell 11 is a hollow cylinder. Specifically, the hollow cylinder is covered with end plates at both ends, and another hollow cylinder with a smaller inner diameter is fitted in the middle of the hollow cylinder. The propeller hub 1 can be fitted and installed on the drive shaft of the aircraft through the hollow cylinder with a smaller inner diameter.

[0030] The fixed ring 12 is fitted inside the housing 11. There is a gap between the outer wall of the fixed ring 12 and the inner wall of the housing 11. Limiting elements or fasteners can be provided for the fixed ring 12 and the housing 11 to fix the fixed ring 12 inside the housing 11.

[0031] The rotating ring 13 is coaxially fitted inside the fixed ring 12 and rotates relative to the axis of the fixed ring 12. A sliding groove 101 is provided on the outer wall of the rotating ring 13, and the extension direction of the sliding groove 101 is inclined relative to the axial direction of the rotating ring 13. A bearing is also fitted between the rotating ring 13 and the fixed ring. The inner diameter of the rotating ring 13 is larger than the small inner diameter of the hollow cylinder of the shell 11, so the small inner diameter hollow cylinder passes through the rotating ring 13.

[0032] One end of the movable base 3 extends outward through the housing 11, and a rear blade root 22 is provided on the outer end of the movable base 3. The other end of the movable base 3 passes through the inner wall of the fixed ring 12 and approaches the outer wall of the moving ring 13. A bushing or shaft sleeve is installed between the movable base 3, the housing 11, and the fixed ring 12. A bearing is provided between the movable base 3 and the shaft sleeve to allow the movable base 3 to rotate smoothly. A sliding pin 31 is eccentrically provided on the end face of the movable base 3 facing the moving ring 13, and the sliding pin 31 is inserted into the sliding groove 101. When the moving ring 13 rotates at a certain angle, the sliding groove 101 will deviate from its previous position, which will drive the sliding pin 31 to move along the sliding groove 101 and also deviate from its original position, thereby driving the movable base 3 and the blade root installed on it to rotate axially.

[0033] exist Figure 3 In a preferred embodiment shown, the device further includes a telescopic drive mechanism 4, a straight rack 5, and an arc rack 6.

[0034] The telescopic drive mechanism 4 is located on the side of the fixed ring 12. The telescopic drive mechanism 4 can be a telescopic pneumatic rod, a hydraulic cylinder, or a nitrogen cylinder.

[0035] The rack 5 is connected to the telescopic drive mechanism 4 and moves along the tangential direction of the moving ring 13 under the drive of the telescopic drive mechanism 4.

[0036] The arc rack 6 is disposed on the side of the moving ring 13. The outer side of the arc rack 6 has teeth that mesh with the straight rack 5. When the telescopic drive mechanism 4 extends, it drives the straight rack 5 to move synchronously and causes the arc rack 6 to rotate around the central axis of the moving ring 13, thus causing the moving ring 13 to rotate synchronously. When the telescopic drive mechanism 4 extends, the moving ring 13 rotates in the opposite direction, causing the movable base 3 to rotate in the opposite direction as well.

[0037] exist Figure 7In a preferred embodiment shown, the two ends of the rear leaf root 22 are a guide edge and a follow edge, respectively. The slide groove 101 extends from the guide edge toward the follow edge along the rotation direction of the moving ring 13. The slide pin 31 in the initial state is located at the end of the slide groove 101 facing the follow edge.

[0038] exist Figure 9 In a preferred embodiment shown, the groove 101 is either a straight groove or an arc groove. When the groove 101 is a straight groove, the greater the slope of the groove 101 relative to the axis of the propeller hub 1, the greater the offset distance of the sliding pin 31 relative to its original position after moving within the groove 101 when the rotating ring 13 rotates at a fixed angle, and thus the greater the rotation angle of the movable base 3. When the groove 101 is an arc groove, its arc protrudes along the rotation direction of the rotating ring 13; and the smaller the arc of the groove 101, the smaller the offset distance of the sliding pin 31 relative to its original position after moving within the groove 101, and thus the smaller the rotation angle of the movable base 3.

[0039] exist Figure 6 In a preferred embodiment shown, a slot 301 is provided on the connection surface between the movable base 3 and the annular blade 2. The movable base 3 is detachably connected to the front blade root 21 or the rear blade root 22 through the slot 301. Specifically, the slot 301 is open at both ends, and a locking block is provided on the contact surface between the front blade root 21 or the rear blade root 22 and the movable base 3. The locking block is slidably locked in the slot 301. Since the movable base 3 is embedded in the housing 11, the housing 11 blocks the slot 301 so that the locking block will not detach from the slot 301.

[0040] The present invention provides a trans-domain vehicle employing a variable-pitch annular propeller according to any of the above embodiments.

[0041] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A variable pitch annular propeller, characterized in that, include: The hub (1) rotates along its axis; At least two annular blades (2) are axially arranged around the hub (1) on the outer circumferential surface of the hub (1); At least two movable bases (3) are embedded in the outer circumferential surface of the propeller hub (1); Among them, the annular blade (2) and the outer peripheral surface of the hub (1) have two connection parts. The two connection parts are arranged in front and back along the axial direction of the hub (1) and are respectively set as the front blade root (21) and the rear blade root (22). The annular blade (2) is made of elastic material and can be twisted and deformed. The movable base (3) is connected to the rear blade root (22). The movable base (3) drives the rear blade root (22) to rotate synchronously along the radial direction of the blade hub (1) relative to the blade hub (1), and causes the annular blade (2) to twist and deform and change the pitch of the annular blade (2).

2. The annular propeller with variable pitch according to claim 1, characterized in that: The movable bases (3) are arranged in pairs, and the two movable bases (3) in each pair are arranged in front and back along the axis of the propeller hub (1). The two movable bases (3) in each pair are connected to the front blade root (21) and the rear blade root (22) respectively.

3. The annular propeller with variable pitch according to claim 2, characterized in that: The anterior leaf root (21) and the posterior leaf root (22) rotate in the same direction.

4. A variable pitch annular propeller according to claim 3, characterized in that: The rotation angle of the posterior leaf root (22) is not less than the rotation angle of the anterior leaf root (21).

5. A variable pitch annular propeller according to claim 1, characterized in that: The propeller hub (1) includes, Shell (11), which is a hollow cylinder; A fixed ring (12) is fitted inside the housing (11); The moving ring (13) is coaxially sleeved inside the fixed ring (12) and rotates relative to the fixed ring (12) axis; One end of the movable base (3) extends outward through the shell (11), and a rear leaf root (22) is provided on the outer end of the movable base (3). The other end of the movable base (3) passes through the inner wall of the fixed ring (12) and approaches the outer wall of the moving ring (13). A sliding pin (31) is eccentrically provided on the end face of the movable base (3) facing the moving ring (13). A groove (101) is provided on the outer wall of the moving ring (13). The extension direction of the groove (101) is inclined relative to the axial direction of the moving ring (13). A sliding pin (31) is inserted in the groove (101).

6. A variable pitch annular propeller according to claim 5, characterized in that, Also includes: The telescopic drive mechanism (4) is disposed on the ring side of the fixed ring (12); A straight rack (5) is connected to the telescopic drive mechanism (4) and moves along the tangential direction of the moving ring (13) under the drive of the telescopic drive mechanism (4); The arc rack (6) is disposed on the ring side of the moving ring (13) and cooperates with the straight rack (5).

7. A variable pitch annular propeller according to claim 5, characterized in that: The two ends of the rear leaf root (22) are the guide edge and the follow edge, respectively. The groove (101) extends from the guide edge toward the follow edge along the rotation direction of the moving ring (13). In the initial state, the sliding pin (31) is located at the end of the groove (101) facing the follow edge.

8. A variable pitch annular propeller according to claim 7, characterized in that: The groove (101) is a straight groove or an arc groove; when the groove (101) is an arc groove, its arc protrudes along the rotation direction of the moving ring (13).

9. A variable pitch annular propeller according to claim 1, characterized in that: The movable base (3) and the annular blade (2) are connected by a slot (301), and the movable base (3) is detachably connected to the front blade root (21) or the rear blade root (22) through the slot (301).

10. A transdomain vehicle, characterized in that: The variable pitch annular propeller described in any one of claims 1 to 9 is used.

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