Annular propeller of cross-domain vehicle, cross-domain vehicle and use method thereof

Abstract

The present invention proposes an annular propeller for a cross-domain aircraft, a cross-domain aircraft, and a method for using the same, which belong to the field of cross-domain aircraft. The portion where the blade is connected to the hub, close to the downstream connection portion, is the rear root portion, and the portion of the blade from the blade tip to the rear root portion is the rear section; the rear section includes a spiral section, a straight section, and a movable section. One end of the spiral section extends to the blade tip and the other end extends toward the rear root portion. The straight section is arranged at the rear root portion and extends straightly toward the free end of the spiral section. One end of the movable section is inserted into the straight section and the other end abuts against the free end of the spiral section. The movable section moves toward the straight section and disengages from the spiral section. The rear root portion of the annular propeller of the present invention has a movable section, which can move and enter the interior of the straight section. By switching the blade between the annular structure and the non-annular structure, the blade does not need to change the propulsion direction according to changes in the navigation environment, and the annular propeller can also be applied to cross-domain navigation drones.

Description

Technical Field

[0001] The present invention relates to the technical field of cross-domain vehicles, and in particular to a ring-shaped propeller of a cross-domain vehicle, a cross-domain vehicle and a method for using the same. Background Art

[0002] Cross-domain vehicles are a new concept capable of cross-domain navigation in various media environments. For example, Chinese patent CN113928068A discloses an underwater-air cross-domain vehicle capable of both underwater and aerial flight. As drone applications expand, cross-domain drones hold even greater promise for both military and civilian applications.

[0003] Drones are primarily propulsive devices for navigation, and the use of annular propellers for drone propulsion is becoming increasingly popular. Compared to conventional non-annular propellers, annular propellers have the advantage of doubling propulsion efficiency with the same number of blades. However, the use of annular propellers in cross-domain drones has encountered several challenges:

[0004] First, the physical properties of water and air are quite different, so the operating state and propulsion performance of the annular propeller in the two media will be significantly different.

[0005] Secondly, when a drone is sailing underwater, the propeller's rotation plane is vertical, providing horizontal propulsion. When a drone is sailing in the air, the propeller's rotation plane can be horizontal, providing vertical lift; or it can be vertical, providing horizontal jet thrust. However, annular propellers are typically used to provide lift and are not suitable for use as propellers providing jet thrust. Therefore, cross-domain navigation drones are not suitable for using annular propellers as a propulsion power source, which also limits the application scenarios of annular propellers. Summary of the Invention

[0006] In view of this, the present invention proposes an annular propeller for a cross-domain aircraft, a cross-domain aircraft and a method of using the same, which solves the problem that cross-domain navigation UAVs are not suitable for using annular propellers as a propulsion power source.

[0007] The technical solution of the present invention is achieved as follows: The present invention provides an annular propeller for a cross-domain vehicle, comprising a hub, a central axis of which is the rotation axis of the annular propeller, and a plurality of blades arranged on the outer peripheral wall of the hub around the central axis; wherein, with the direction of the annular propeller toward the downstream as the first direction, there are two parts where the blades are connected to the hub, and the two connection parts are spaced apart along the first direction, the connection part close to the downstream is the rear root, and the part of the blade from the blade tip to the rear root is the rear section; the rear section includes a spiral section, a straight section and a movable section, one end of the spiral section extends to the blade tip and the other end extends toward the rear root, the straight section is arranged at the rear root and extends straightly toward the free end of the spiral section, the straight section is a hollow cylinder, the movable section is arranged between the spiral section and the straight section, one end of the movable section is inserted in the straight section and the other end abuts against the free end of the spiral section, the movable section moves relative to the hub along the extension direction of the straight section, so that the movable section moves toward the straight section and disengages from the spiral section.

[0008] On the basis of the above technical solution, preferably, it further includes a telescopic mechanism, which is arranged in the straight section; wherein the telescopic mechanism is connected to the end of the movable section inserted in the straight section, and the telescopic mechanism drives the movable section to move relative to the hub.

[0009] On the basis of the above technical solution, preferably, the connecting portion between the blade and the hub close to the upstream is the front root, the part of the blade from the blade tip to the front root is the front section, the rotation direction of the annular propeller is the second direction, the side edge of the front section along the second direction is the leading edge, and the side edge of the rear section facing away from the second direction is the trailing edge; in the radial section of the annular propeller, a circle is drawn with the central axis as the center and the circle intersects the leading edge and the trailing edge at two points, the maximum distance between the two points is the width L of the blade, the distance from the blade tip to the central axis is the radius R of the blade, and the ratio of R:L is 0.8~1.

[0010] More preferably, in the radial section of the annular propeller, the distance between the free end of the spiral segment and the outer peripheral wall of the hub is no more than 1 / 3R.

[0011] On the basis of the above technical solution, preferably, a tip portion is provided on the free end of the spiral segment, and the outer contour of the tip portion is a sheet-like streamlined shape; a matching groove is provided on the free end of the movable segment, and the inner contour of the matching groove matches the outer contour of the tip portion, so that when the movable segment and the spiral segment are in contact, the tip portion is inserted and wrapped in the matching groove.

[0012] On the basis of the above technical solution, preferably, a groove is provided on the outer peripheral wall of the hub; and the straight section is arranged in the groove.

[0013] More preferably, after the movable section moves and enters the straight section, the outer end surface of the straight section and the outer end surface of the free end of the movable section are flush with the outer peripheral wall of the hub.

[0014] Based on the above technical solution, preferably, the number of blades is a prime number.

[0015] In a second aspect, the present invention further provides a cross-domain vehicle that sails on the water surface or underwater and uses the above-mentioned annular propeller of the cross-domain vehicle, and the number of annular propellers used in the cross-domain vehicle is at least one.

[0016] In a third aspect, the present invention also provides a method for using a cross-domain vehicle, which adopts the above-mentioned cross-domain vehicle; when the cross-domain vehicle is sailing underwater, the movable section is in contact with the spiral section; when the cross-domain vehicle is sailing on the water surface and a part of any blade is located above the water surface, the movable section moves into the straight section and disengages from the spiral section.

[0017] The annular propeller of the cross-domain vehicle, the cross-domain vehicle and the method of using the same have the following advantages over the prior art:

[0018] (1) The annular propeller of the present invention has a movable section at the rear root, which can move and enter the inside of the straight section. When the aircraft is sailing underwater, the movable section and the spiral section are kept in contact, so that the blades are in an annular structure to improve the propulsion efficiency. When the aircraft is sailing in the air, the movable section and the spiral section are disengaged, so that the blades are switched from an annular structure to a non-annular structure. The blades provide jet propulsion power for the UAV instead of lift, so that the blades do not need to change the propulsion direction according to changes in the navigation environment. By switching the blades between the annular structure and the non-annular structure, the annular propeller can also be applied to cross-domain navigation UAVs, thereby improving the versatility of the annular propeller.

[0019] (2) The rotation radius and maximum width of the annular blade of the present invention have a certain ratio. On the basis of ensuring that the blade has sufficient length to provide propulsion, the maximum width of the blade should not be too small, which will cause the blade to have a slender shape. This will cause the movable section to retreat into the straight section, so that the blade switches to a non-annular structure. The overall structural strength of the slender blade will be greatly reduced. Therefore, the above-mentioned risk is avoided by designing the ratio of the rotation radius and the maximum width of the blade.

[0020] (3) The free end of the spiral segment of the present invention is provided with a sheet-like streamlined tip portion, and the movable segment is matched with the tip portion through a matching groove. On the one hand, when the movable segment abuts against the spiral segment, the tip portion is wrapped in the matching groove to form a wedge connection structure, which helps to enhance the connection strength between the movable segment and the spiral segment. On the other hand, when the blade switches to a non-annular structure, the tip portion helps to reduce the resistance encountered by the blade during rotation and improve the airflow environment during blade rotation, which helps to enhance the propulsion efficiency of the propeller. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0022] Figure 1 is a perspective view of the annular propeller of the present invention;

[0023] Figure 2 A perspective view of the annular propeller of the present invention from another perspective;

[0024] Figure 3 A perspective view of the annular propeller of the present invention from another perspective;

[0025] Figure 4 This is a front view comparison diagram of the state change of the annular propeller of the present invention;

[0026] Figure 5 A cross-sectional comparison diagram of the state change of the latter section of the present invention;

[0027] Figure 6 It is a cross-sectional view of another embodiment of the latter section of the present invention.

[0028] In the figure: 1. hub; 2. blade; 21. rear section; 22. front section; 211. spiral section; 212. straight section; 213. movable section; 214. tip; 201. rear root; 202. front root; 203. matching groove; 204. groove; 3. telescopic mechanism. DETAILED DESCRIPTION

[0029] 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.

[0030] like Figure 1 As shown, combined Figure 2 and Figure 4 The annular propeller of a cross-domain vehicle of the present invention comprises

[0031] The central axis of the hub 1 is the rotation axis of the annular propeller.

[0032] A plurality of blades 2 are arranged around the central axis on the outer peripheral wall of the hub 1. With the downstream direction of the annular propeller as the first direction, there are two locations where the blade 2 is connected to the hub 1, and the two connection locations are spaced apart along the first direction. The connection location closest to the downstream is the rear root 201, and the portion of the blade 2 from the blade tip to the rear root 201 is the rear section 21. The purpose of this scheme is to design a propeller that can switch between an annular structure and a non-annular structure. One feasible implementation method is to design a movable portion at the rear root 201 of the annular blade 2. Through the displacement of this movable portion, the blade 2 can switch between a completed annular structure and a broken ring structure with a gap.

[0033] Specifically, the rear section 21 includes a spiral section 211 , a straight section 212 and a movable section 213 .

[0034] Among them, one end of the spiral segment 211 extends to the blade tip and the other end extends toward the rear root 201. The spiral segment 211 extends along the spiral busbar during the extension process. Therefore, if the movable part is a part of the spiral segment 211, then the structure of the movable part is difficult to design and its movable range is also difficult to control.

[0035] Therefore, the inventors thought about whether it is possible to add a section of the blade 2 at the rear root 201. This section extends straight. On the one hand, it will not affect the extension state of the spiral section 211 along the spiral generatrix. On the other hand, this straight extension section can be split into a fixed part and a movable part, thus realizing the switching of the blade 2 between a complete ring and a broken ring. Specifically, the straight section 212 is arranged at the rear root 201 and extends straightly toward the free end of the spiral section 211. The straight section 212 is a hollow cylinder; and the movable section 213 is arranged between the spiral section 211 and the straight section 212. When the blade 2 is a ring structure, one end of the movable section 213 is inserted into the straight section 212 and the other end is in contact with the free end of the spiral section 211. When the blade 2 is a broken ring structure, the movable section 213 moves relative to the hub 1 along the extension direction of the straight section 212, so that the movable section 213 moves toward the straight section 212 and breaks contact with the spiral section 211. By adopting the above design, the blade 2 can realize the function of switching between the annular structure and the non-annular structure, and the annular propeller can also be applied to cross-domain navigation drones, thereby improving the versatility of the annular propeller.

[0036] exist Figure 5 In a preferred embodiment shown, in order to drive the movable section 213 to move, a telescopic mechanism 3 is also included.

[0037] The telescopic mechanism 3 is disposed within the straight section 212; it can be a hydraulic telescopic rod, a telescopic pneumatic rod, or a telescopic electric rod. The telescopic mechanism 3 is connected to the movable section 213, which is inserted into the end of the straight section 212. The telescopic mechanism 3 drives the movable section 213 to move relative to the hub 1. Furthermore, a locking mechanism is provided within the straight section 212 to lock the movable section 213 in place, eliminating the need to use the telescopic mechanism 3 to maintain the movable section 213 in place.

[0038] exist Figure 4 In a preferred embodiment shown, Figure 3 This solution is not applicable to all types of annular propellers, especially slender annular blades 2. The reason is that although this solution can be used to switch the annular and non-annular structures of an slender annular blade 2, when it is deformed into a non-annular structure, its rear section 21 is long and is only connected to the front section 22 at the blade tip. At this time, the structural strength of the slender blade 2 is very poor. Once it starts to rotate, the rear section 22 of the blade 2 will break due to factors such as centrifugal force and wind resistance. It can be seen that the ratio of the diameter to width of the annular blade 2 applicable to this case should not be too large. Specifically, the connection point between the blade 2 and the hub 1 near the upstream is the front root 202, and the portion of the blade 2 from the blade tip to the front root 202 is the front section 22. Taking the rotation direction of the annular propeller as the second direction, the side edge of the front section 22 along the second direction is the leading edge, and the side edge of the rear section 21 facing away from the second direction is the trailing edge.

[0039] If in the radial section of the annular propeller, a circle is drawn with the central axis as the center and the circle intersects with the leading edge and the trailing edge at two points, the maximum distance between the two points is the width L of the blade 2, the distance from the tip of the blade 2 to the central axis is the radius R of the blade 2, and the ratio of R:L is 0.8 to 1. At this time, the ratio of the diameter length to the width of the blade 2 is between 1:1 and 5:4, and the blade 2 has a structure similar to a circle or an ellipse. At this time, the blade 2 has good structural strength even after forming a broken ring.

[0040] exist Figure 4 In a preferred embodiment shown, in order to further improve the structural strength of the blade 2 after switching to the broken ring structure, in the radial section of the annular propeller, the distance between the free end of the spiral segment 211 and the outer peripheral wall of the hub 1 is not greater than 1 / 3R, so the extension length of the spiral segment 211 is not too long, thereby avoiding the probability of it breaking during rotation; in addition, at this time, the hook structure formed by the spiral segment 211 at the rear section 21 is also shorter, making the shape of the blade 2 more similar to that of a conventional non-annular propeller, which helps to reduce the noise generated by the blade 2 during rotation.

[0041] exist Figure 5In a preferred embodiment shown, to reduce the wind resistance that may be experienced by blade 2 after switching to a broken-ring structure, a tip portion 214 is provided on the free end of spiral segment 211. The outer contour of tip portion 214 is a streamlined, sheet-like shape. Tip portion 214 helps reduce the resistance encountered by blade 2 during rotation and improves the airflow environment during rotation, thereby enhancing the propeller's propulsion efficiency. A mating groove 203 is provided on the free end of movable segment 213. The inner contour of mating groove 203 matches the outer contour of tip portion 214, so that when movable segment 213 abuts spiral segment 211, tip portion 214 is inserted into and wrapped in mating groove 203. Tip portion 214 wrapped in mating groove 203 forms a wedge-type connection structure, which helps to enhance the connection strength between movable segment 213 and spiral segment 211.

[0042] exist Figure 6 In a preferred embodiment shown, a groove 204 is provided on the outer peripheral wall of the hub 1; the straight section 212 is arranged in the groove 204 to prevent the straight section 212 from protruding from the outer peripheral wall of the hub 1 to form a blade similar to a shorter blade 2, thereby avoiding increasing the blade frequency noise of the propeller.

[0043] exist Figure 6 In the preferred embodiment shown, specifically, after the movable segment 213 moves and enters the straight segment 212, the outer end surface of the straight segment 212 and the outer end surface of the free end of the movable segment 213 are flush with the outer circumferential wall of the hub 1. Therefore, assuming that when the blades 2 have an annular structure, there are three blades 2, then when it switches to a non-annular structure, the number of blades 2 remains three.

[0044] exist Figure 1 In a preferred embodiment shown, the number of blades 2 is a prime number. Avoiding an even number of blades 2 can significantly reduce the modes generated by propeller rotation. The reason is the same as that the blades 2 of a traditional non-annular propeller are usually also a prime number.

[0045] like Figure 1 As shown, a cross-domain vehicle of the present invention sails on the water surface or underwater and adopts the above-mentioned annular propeller of the cross-domain vehicle, and the number of the annular propeller adopted by the cross-domain vehicle is at least one.

[0046] like Figure 1 As shown, combined Figure 4, a method for using a cross-domain vehicle of the present invention adopts the above-mentioned cross-domain vehicle; when the cross-domain vehicle is sailing underwater, the movable section 213 abuts against the spiral section 211, and the blade 2 is an annular structure at this time, so that the vehicle uses an annular propeller when sailing in an underwater environment. Compared with a non-annular propeller, the annular propeller can provide greater propulsion and reduce blade frequency noise; when the cross-domain vehicle is sailing on the water surface and a part of any blade 2 is located above the water surface, the movable section 213 moves into the straight section 212 and disengages from the spiral section 211, so that the blade 2 switches to a non-annular structure. At this time, the propeller does not need to change the thrust direction to provide horizontal jet thrust for the vehicle to sail in the air.

[0047] 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 in the scope of protection of the present invention.

Claims

1. A ring propeller for a cross-domain vehicle, characterized in that: include: A hub (1), the central axis of which is the rotation axis of the annular propeller, A plurality of blades (2) are arranged on the outer peripheral wall of the hub (1) around the central axis; Wherein, with the direction of the annular propeller toward the downstream being the first direction, there are two connection locations between the blade (2) and the hub (1), and the two connection locations are spaced apart along the first direction, the connection location close to the downstream being the rear root (201), and the portion of the blade (2) from the blade tip to the rear root (201) being the rear section (21); The rear section (21) comprises a spiral section (211), a straight section (212) and a movable section (213); one end of the spiral section (211) extends to the blade tip and the other end extends toward the rear root (201); the straight section (212) is arranged at the rear root (201) and extends straightly aligned with the free end of the spiral section (211); the straight section (212) is a hollow cylinder; the movable section (213) is arranged between the spiral section (211) and the straight section (212); one end of the movable section (213) is inserted into the straight section (212) and the other end abuts against the free end of the spiral section (211); the movable section (213) moves relative to the hub (1) along the extension direction of the straight section (212), so that the movable section (213) moves toward the straight section (212) and is out of contact with the spiral section (211); The connecting portion of the blade (2) and the hub (1) close to the upstream is the front root (202), the portion of the blade (2) from the blade tip to the front root (202) is the front section (22), the rotation direction of the annular propeller is the second direction, the side edge of the front section (22) along the second direction is the leading edge, and the side edge of the rear section (21) facing away from the second direction is the trailing edge; In the radial section of the annular propeller, a circle is drawn with the central axis as the center and the circle intersects with the leading edge and the trailing edge at two points, the maximum distance between the two points is the width L of the blade (2), the distance from the tip of the blade (2) to the central axis is the radius R of the blade (2), and the ratio of R:L is 0.8~1.

2. The annular propeller of a cross-domain vehicle according to claim 1, characterized in that: Also includes: a telescopic mechanism (3) disposed in the straight section (212); The telescopic mechanism (3) is connected to the movable section (213) inserted into the end of the straight section (212), and the telescopic mechanism (3) drives the movable section (213) to move relative to the propeller hub (1).

3. The annular propeller of a cross-domain vehicle according to claim 2, characterized in that: In the radial section of the annular propeller, the distance between the free end of the spiral segment (211) and the outer peripheral wall of the hub (1) is no greater than 1 / 3R.

4. The annular propeller of a cross-domain vehicle according to claim 1, characterized in that: A tip portion (214) is provided on the free end of the spiral segment (211), and the outer contour of the tip portion (214) is a sheet-like streamlined shape; A matching groove (203) is provided on the free end of the movable section (213), and the inner contour of the matching groove (203) matches the outer contour of the tip portion (214), so that when the movable section (213) abuts against the spiral section (211), the tip portion (214) is inserted into and wrapped in the matching groove (203).

5. The annular propeller of a cross-domain vehicle according to claim 1, characterized in that: A groove (204) is provided on the outer peripheral wall of the hub (1); and the straight section (212) is arranged in the groove (204).

6. The annular propeller of a cross-domain vehicle according to claim 5, characterized in that: After the movable section (213) moves and enters the straight section (212), the outer end surface of the straight section (212) and the outer end surface of the free end of the movable section (213) are flush with the outer peripheral wall of the hub (1).

7. The annular propeller of a cross-domain vehicle according to claim 1, characterized in that: The number of the blades (2) is a prime number.

8. A cross-domain vehicle, characterized by: Sailing on the water surface or underwater, and using the annular propeller of the cross-domain vehicle according to any one of claims 1 to 7, the number of the annular propeller used in the cross-domain vehicle is at least one.

9. A method for using a cross-domain vehicle, characterized by: Using a cross-domain navigation vehicle as described in claim 8; When the cross-domain vehicle is navigating underwater, the movable segment (213) abuts against the spiral segment (211); When the cross-domain vehicle is sailing on the water surface and a portion of any of the blades (2) is located above the water surface, the movable section (213) moves into the straight section (212) and breaks away from contact with the spiral section (211).

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