Unfoldable annular propeller and cross-domain aircraft

Abstract

The invention provides a deployable annular propeller and a cross-domain aircraft, and belongs to the field of annular propellers, the deployable annular propeller comprises a propeller hub, blades and a locking part, the blades are made of flexible materials, the blades are bent and deformed into a first form or rebound and reset into a second form, one end of each blade is fixedly connected with the peripheral wall of the propeller hub and is set as a root part, and the other end of each blade is set as a locking part; the other end of the paddle is a free end and is arranged as a tip part; the paddle is in a first form and is bent into a ring shape, and the tip part is connected with the locking part; and the locking part releases the tip part, and the paddle is switched to the second state. The annular propeller blades are made of the flexible materials and can elastically deform, the propeller blades are bent to be annular, the tip parts of the propeller blades are fixed to the locking parts, and the formed annular propeller is more suitable for the underwater navigation scene of a cross-domain aircraft; and when the tip parts of the paddles are separated from the control of the locking parts, the paddles are reset and deformed into non-annular propellers, so that the propeller is more suitable for the scene that the cross-domain aircraft sails in the air, and the paddles have the capability of switching from an annular structure to a non-annular structure.

Description

Technical Field

[0001] The present invention relates to the technical field of cross-domain vehicles, and in particular to a deployable annular propeller and a cross-domain vehicle. Background Art

[0002] Cross-domain aircraft is a new concept aircraft that can navigate across domains in a variety of media environments. For example, Chinese patent CN113928068A discloses an underwater-air cross-domain aircraft that can dive underwater and fly in the air. In particular, at a time when drones are increasingly widely used, cross-domain navigation drones have a broader application prospect in military and civilian applications.

[0003] The drone can fly, and the main propulsion role is played by the propeller; currently, the use of annular propellers for propulsion on drones has gradually become a hot topic. Compared with conventional non-annular propellers, the advantage of annular propellers is that their propulsion efficiency can be doubled with the same number of blades. However, the application of annular propellers on cross-domain navigation drones has encountered some problems:

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

[0005] Secondly, when the drone is sailing underwater, the propeller's rotating surface is vertical and provides horizontal propulsion. When the drone is sailing in the air, the propeller's rotating surface can be horizontal and provide vertical lift; the propeller's rotating surface can also be vertical and provide horizontal jet thrust. However, annular propellers are usually used as propellers to provide lift, and are not suitable for use as propellers to provide 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 a deployable annular propeller and a cross-domain navigation vehicle, 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 implemented as follows: the present invention provides a deployable annular propeller, comprising a hub, whose central axis is the rotation axis of the annular propeller, a plurality of blades, which are arranged on the outer peripheral wall of the hub around the central axis; a locking portion, which is arranged on the outer peripheral wall of the hub; wherein the blade is made of flexible material, the blade is bent and deformed into a first form or rebounds to a second form, one end of the blade is fixedly connected to the outer peripheral wall of the hub and is set as a root, and the other end of the blade is a free end and is set as a tip; the blade is in the first form and is bent into a ring, and the tip is connected to the locking portion; the locking portion releases the tip, and the blade switches to the second form.

[0008] On the basis of the above technical solution, preferably, the tip portion and the locking portion are connected by an explosive bolt.

[0009] On the basis of the above technical solution, preferably, a slot is opened on the outer peripheral wall of the hub, and a locking part is arranged in the slot; the blade is in a first form and bent into a ring shape, and the tip is inserted into the slot and connected to the locking part; the blade switches to the second form and the tip exits the slot.

[0010] Further preferably, the paddle comprises a blade, one end of which is fixedly connected to the outer peripheral wall of the hub and the other end extends to form a tip; a bone rod, which is inserted into the blade and has one end fixedly connected to the outer peripheral wall of the hub and the other end extending to the end of the tip; wherein the blade is made of a flexible material and can be elastically deformed; the bone rod is made of a one-way shape memory alloy, and the tip is connected to a locking portion, so that the bone rod is bent and deformed by force and drives the blade to deform accordingly, so that the blade is in a first form; the locking portion releases the tip, the bone rod is heated to deform due to the one-way memory effect and drives the blade to deform again, so that the blade switches to a second form.

[0011] More preferably, it also includes a heating mechanism, which is arranged in the propeller hub and electrically connected to the bone rod; wherein the heating mechanism is used to heat the bone rod and cause the bone rod to deform with a one-way memory effect.

[0012] More preferably, when the blade is bent into a ring shape, the inner ring contour of the ring is used as the inner edge, and the bone rod is inserted into the blade along the inner edge.

[0013] Further preferably, the locking portion includes two telescopic mechanisms, which are symmetrically arranged in the slot and respectively aligned with the two blade surfaces of the tip; two clamping blocks, which are respectively connected to the two telescopic mechanisms and move toward or away from the blade surfaces of the tip under the drive of the telescopic mechanisms; wherein the two clamping blocks move toward each other at the same time and clamp the tip, or the two clamping blocks move away from each other at the same time and release the tip.

[0014] More preferably, the locking portion further includes a cable mechanism, which is arranged at the bottom of the slot; wherein a through hole is opened in the blade, one end of the through hole is connected to the outside, and the other end of the through hole extends toward the free end of the bone rod and exposes the end of the bone rod; the cable mechanism is connected to the end of the bone rod by a pull rope passing through the through hole, and the cable mechanism pulls the bone rod through the pull rope and causes the bone rod to deform under force, or the cable mechanism releases the pull rope.

[0015] On the basis of the above technical solution, preferably, the direction of the annular propeller toward downstream is taken as the positive direction, the root is arranged at a portion of the hub close to the downstream, and the tip is bent into a ring shape toward a portion of the hub close to the upstream.

[0016] On the other hand, the present invention also provides a cross-domain vehicle, which adopts the above-mentioned deployable annular propeller; when the cross-domain vehicle is sailing underwater, the blades are in a first form and bent into a ring, and the tip is connected to the locking part; when the cross-domain vehicle is sailing in the air, the locking part releases the tip, and the blades switch to the second form.

[0017] Compared with the prior art, the deployable annular propeller and cross-domain vehicle of the present invention have the following advantages:

[0018] Beneficial effects:

[0019] (1) The annular propeller blades of the present invention are made of flexible materials and can be elastically deformed. By bending the blades into a ring and fixing their tips on a locking portion, the formed annular propeller is more suitable for scenarios where cross-domain vehicles are sailing underwater. When the tip of the blades is released from the control of the locking portion, the blades are restored and deformed into a non-annular propeller, which is more suitable for scenarios where cross-domain vehicles are sailing in the air. By enabling the blades to switch from an annular structure to a non-annular structure according to the switching of cross-domain scenarios, the versatility of the annular propeller is improved.

[0020] (2) The present invention inserts a bone rod made of a one-way shape memory alloy into the blade of the propeller. The bone rod is deformed and bent under stress and reset after being heated, thereby realizing the function of converting the propeller from an annular structure to a non-annular structure. The present invention is suitable for propellers made of metal or plastic materials.

[0021] (3) The cross-domain vehicle of the present invention only crosses from water to air, so there is no need to consider the problem of the blades being converted from an annular structure to a non-annular structure and then retracted. Therefore, the present invention achieves a one-way shape change of the annular propeller through the variable design of the blades, thereby improving the applicability and versatility of the annular propeller in the cross-domain vehicle. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. 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 creative work.

[0023] Figure 1 is a perspective view of an annular propeller of the present invention;

[0024] Figure 2 is a partial cross-sectional view of the blade tip of the present invention;

[0025] Figure 3 is a perspective view of another embodiment of the annular propeller of the present invention;

[0026] Figure 4 is a side view of another embodiment of the annular propeller of the present invention;

[0027] Figure 5 is a top sectional view of another embodiment of the annular propeller of the present invention;

[0028] Figure 6 is a partial top sectional view of a blade of the present invention;

[0029] Figure 7 for Figure 6 The enlarged view of point A in the middle;

[0030] Figure 8 It is a partial cross-sectional view of the locking portion of the present invention.

[0031] In the figure: 1. hub; 101. slot; 2. blade; 21. blade; 22. rod; 201. root; 202. tip; 203. through hole; 3. locking part; 31. telescopic mechanism; 32. clamping block; 33. cable mechanism; 301. explosive bolt; 4. heating mechanism. DETAILED DESCRIPTION

[0032] 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 described embodiments 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 creative work are within the scope of protection of the present invention.

[0033] like Figure 1 As shown, a deployable annular propeller of the present invention comprises a hub 1, blades 2 and a locking portion 3.

[0034] The central axis of the hub 1 is the rotation axis of the annular propeller.

[0035] A plurality of blades 2 are arranged on the outer peripheral wall of the hub 1 around the central axis. The blades 2 are made of a flexible material, specifically, a shape memory alloy material, so the blades 2 have the ability to bend and deform into a first form or rebound and reset to a second form. One end of the blade 2 is fixedly connected to the outer peripheral wall of the hub 1 and is set as a root 201, and the other end of the blade 2 is a free end and is set as a tip 202. Since the blade 2 needs to have good deformation performance, and the blade 2 still has a good streamlined outer contour after deformation when the blade 2 switches between the first form and the second form, the thickness of the blade 2 needs to be thin and plate-shaped.

[0036] The locking part 3 is arranged on the outer peripheral wall of the hub 1. The blade 2 is in the first state and is bent into a ring shape, and the tip 202 is connected to the locking part 3; the locking part 3 releases the tip 202, and the blade 2 switches to the second state.

[0037] According to the principle of the present invention, when the blade 2 is connected to the locking portion 3 at the tip 202, the blade 2 is an annular propeller structure and is in the first form. At this time, the annular propeller is suitable for scenes of sailing in water; and after the navigation scene of the cross-domain vehicle changes, the locking portion 3 releases the tip 202, which can be regarded as the annular structure of the blade 2 being disconnected at the tip 202, so that the blade 2 can switch to the second form through deformation, and the blade 2 in the second form is transformed into a non-annular structure. At this time, the annular propeller is suitable for scenes of sailing in the air. However, in this solution, the blade 2 only has the ability to transform from the first annular form to the second non-annular form to expand and deform, but does not have the ability to retract. Therefore, when the annular propeller of the present application is used on a cross-domain vehicle, the cross-domain vehicle only needs to consider the situation of sailing from water to air, without considering the situation of the vehicle returning to the water to sail.

[0038] exist Figure 2 In a preferred embodiment shown, in order to realize the switchable performance of the connection state between the tip 202 of the blade 2 and the locking part 3 being fixed or separated, the tip 202 and the locking part 3 are connected by an explosive bolt 301. The explosive bolt 301 is a connecting bolt between a booster and a rocket body used in the aerospace field. In addition, the connection method of this embodiment is suitable for the case where the blade 2 is made of metal; the blade 2 of this embodiment has good structural strength and is suitable for large aircraft.

[0039] exist Figure 3 In a preferred embodiment shown, the tip 202 of the blade 2 and the locking portion 3 have another connection method, a slot 101 is provided on the outer peripheral wall of the hub 1, and the locking portion 3 is arranged in the slot 101; the blade 2 is in a first form and bent into a ring, the tip 202 is inserted into the slot 101 and connected with the locking portion 3; the blade 2 switches to a second form and the tip 202 is withdrawn from the slot 101. The connection method of this embodiment is suitable for the case where the blade 2 is made of plastic material or high molecular polymer material.

[0040] exist Figure 6 In a preferred embodiment shown, in order to make the blade 2 have deformation performance and at the same time make the blade 2 have good structural strength to avoid structural deformation of the blade 2 during high-speed rotation, the blade 2 includes a blade 21 and a rod 22.

[0041] One end of the blade 21 is fixedly connected to the outer peripheral wall of the hub 1 and the other end extends to form a tip 202. The blade 21 is made of a flexible material and can be elastically deformed. It has high elasticity and plasticity. Specifically, styrene thermoplastic elastomer TPS, olefin thermoplastic elastomer TPO, TPV, etc. can be used.

[0042] The bone rod 22 is inserted into the blade 21, one end of the bone rod 22 is fixedly connected to the outer peripheral wall of the hub 1 and the other end extends to the end of the tip 202. The bone rod 22 is made of a one-way shape memory alloy, which is a nickel-titanium shape memory alloy material such as titanium-nickel-copper, titanium-nickel-iron, titanium-nickel-chromium, etc., and can also be made of copper-nickel alloy, copper-aluminum alloy, copper-zinc alloy, iron alloy, etc. When the blade 2 is initially in an annular structure, the tip 202 is connected to the locking portion 3, so that the bone rod 22 is bent and deformed by force and drives the blade 21 to deform accordingly, so that the blade 2 is in the first form; and when the locking portion 3 releases the tip 202, the bone rod 22 is heated to produce a one-way memory effect deformation and drives the blade 21 to deform again, so that the blade 2 switches to the second form; because the bone rod 22 is made of a one-way shape memory alloy material, after the temperature drops, the bone rod 22 will not be affected by external force and will not shrink again to its state of bending deformation by force, so that the blade 2 has a non-annular structure.

[0043] exist Figure 6 In a preferred embodiment shown, a heating mechanism 4 is also included to increase the temperature of the bone rod 22 to deform it.

[0044] The heating mechanism 4 is a thermocouple, which is disposed in the propeller hub 1 and electrically connected to the bone rod 22; the heating mechanism 4 is used to heat the bone rod 22 and cause the bone rod 22 to deform due to a one-way memory effect. In order to prevent the heating mechanism 4 from having an adverse effect on the propeller hub 1 when it is working, the heating mechanism 4 is wrapped in a heat-insulating material and then installed in the propeller hub 1.

[0045] exist Figure 6 In a preferred embodiment shown, when the blade 2 is bent into a ring shape, the inner ring contour of the ring is used as the inner edge, and the bone rod 22 is inserted into the blade 21 along the inner edge. Under this design, the bone rod 22 is closer to the inner edge of the ring-shaped blade 2, so the length of the bone rod 22 is shorter; at the same time, after the blade 2 is deformed into a non-ring structure, the bone rod 22 is closer to the trailing edge position of the blade 2. On the one hand, it can be regarded as the spine of the blade 2 at this time, so that the blade 2 has better structural strength. On the other hand, the trailing edge thickness of the blade 2 is larger than the leading edge thickness, which also avoids setting the bone rod 22 on the leading edge of the blade 2, resulting in an increase in the thickness of the leading edge, thereby reducing the effect of the streamlined outer contour of the blade 2 complying with the rotation direction of the propeller.

[0046] exist Figure 8In a preferred embodiment shown, when the tip 202 of the blade 2 is inserted into the slot 101 , in order to fix the annular structure of the blade 2 , the locking portion 3 includes a telescopic mechanism 31 and a clamping block 32 .

[0047] The two telescopic mechanisms 31 are symmetrically arranged in the slot 101 and are respectively aligned with the two blade surfaces of the tip 202. The telescopic mechanism 31 may be a telescopic gas rod.

[0048] The two clamping blocks 32 are connected to the two telescopic mechanisms 31 respectively and move toward or away from the blade surface of the tip 202 under the drive of the telescopic mechanisms 31; the two clamping blocks 32 move toward each other at the same time and clamp the tip 202, or the two clamping blocks 32 move away from each other at the same time and release the tip 202. In order to avoid damage to the blade 2, the clamping blocks 32 can be rubber blocks.

[0049] exist Figure 7 In a preferred embodiment shown, if the blade 2 is fixed by clamping it only by two clamping blocks 32, the blade 2 is actually locked by friction at this time, and it is difficult to avoid the problem that the tip 202 of the blade 2 is disengaged from the slot 101 due to centrifugal force during the rotation of the blade 2. The locking part 3 also includes a cable mechanism 33.

[0050] A through hole 203 is defined in the blade 21 , one end of the through hole 203 is connected to the outside, and the other end of the through hole 203 extends toward the free end of the bone rod 22 and exposes the end of the bone rod 22 .

[0051] The cable mechanism 33 is arranged at the bottom of the slot 101. The cable mechanism 33 is connected to the end of the bone rod 22 through a cable passing through the through hole 203. The cable mechanism 33 pulls the bone rod 22 through the cable to cause the bone rod 22 to deform under stress, or the cable mechanism 33 releases the cable.

[0052] exist Figure 4 In a preferred embodiment shown, the direction of the annular propeller toward the downstream is taken as the positive direction, the root 201 is arranged at the part of the hub 1 close to the downstream, and the tip 202 is bent into an annular shape toward the part of the hub 1 close to the upstream. At this time, the root 201 and the tip 202 can be regarded as the front blade root and the rear blade root of the annular blade 2. Generally speaking, the blade 2 is restricted to be disconnected from its rear blade root (i.e., the tip 202) and deformed into a non-annular structure. At this time, the leading edge and the trailing edge of the original annular blade 2 are simultaneously transformed into the leading edge of the non-annular blade 2, and the inner ring contour edge of the original annular blade 2 is transformed into the trailing edge of the non-annular blade 2. At this time, the streamlined outer contour of the non-annular blade 2 complies with the rotation direction of the propeller. If the blade 2 is disconnected from its front blade root (i.e., the root 201) and deformed into a non-annular structure, the leading edge and the trailing edge of the original annular blade 2 will be simultaneously transformed into the trailing edge of the non-annular blade 2, so that the streamlined outer contour of the non-annular blade 2 opposes the rotation direction of the propeller.

[0053] like Figure 1 As shown, combined Figure 5 , a cross-domain vehicle of the present invention adopts a deployable annular propeller of any of the above-mentioned embodiments; the cross-domain vehicle mainly refers to a water-air cross-domain vehicle, specifically a drone that first sails underwater and then enters the air from the water. After that, the drone can dock on land or on the deck of a ship, so there is no need to consider the situation where the drone returns to the water from the air to sail. Therefore, when the cross-domain vehicle is sailing underwater, the blade 2 is in the first form and bent into a ring, and the blade 2 forms an annular propeller structure, at which time the tip 202 is connected to the locking part 3; and when the cross-domain vehicle needs to cross the domain to sail in the air, the locking part 3 releases the tip 202, so that the tip 202 of the blade 2 is unlocked, and the blade 2 switches to the second form, so that the blade 2 forms a non-annular structure; afterwards, because the vehicle will not return to the water, the blade 2 does not need to have the ability to deform from the non-annular structure to the annular structure.

[0054] 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 protection scope of the present invention.

Claims

1. A deployable annular propeller, 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 a central axis; A locking portion (3) is arranged on the outer peripheral wall of the hub (1); The blade (2) is made of a flexible material, the blade (2) is bent and deformed into a first shape or rebounds and resets into a second shape, one end of the blade (2) is fixedly connected to the outer peripheral wall of the hub (1) and is set as a root (201), and the other end of the blade (2) is a free end and is set as a tip (202); The blade (2) is in a first state and is bent into a ring shape, and the tip (202) is connected to the locking portion (3); The locking portion (3) releases the tip (202), and the paddle (2) switches to the second form.

2. A deployable annular propeller according to claim 1, characterized in that: The tip portion (202) and the locking portion (3) are connected via an explosive bolt (301).

3. The deployable annular propeller according to claim 1, characterized in that: A slot (101) is provided on the outer peripheral wall of the hub (1), and a locking portion (3) is provided in the slot (101); The blade (2) is in a first state and is bent into a ring shape, and the tip (202) is inserted into the slot (101) and connected to the locking portion (3); The paddle (2) switches to the second configuration and causes the tip (202) to exit the slot (101).

4. A deployable annular propeller according to claim 3, characterized in that: The blade (2) comprises: A blade (21), one end of which is fixedly connected to the outer peripheral wall of the hub (1) and the other end of which extends to form a tip (202); A bone rod (22) is inserted into the blade (21), one end of which is fixedly connected to the outer peripheral wall of the hub (1) and the other end of which extends to the end of the tip (202); Wherein, the blade (21) is made of a flexible material and can be elastically deformed; The bone rod (22) is made of a one-way shape memory alloy, and the tip (202) is connected to the locking portion (3), so that the bone rod (22) is bent and deformed under force and drives the blade (21) to deform accordingly, so that the blade (2) is in a first shape; When the locking portion (3) releases the tip (202), the bone rod (22) is heated to deform due to a one-way memory effect and drives the blade (21) to deform again, so that the blade (2) switches to the second form.

5. A deployable annular propeller according to claim 4, characterized in that: Also includes: A heating mechanism (4) is arranged in the hub (1) and is electrically connected to the bone rod (22); Wherein, the heating mechanism (4) is used to heat the bone rod (22) and cause the bone rod (22) to deform in a one-way memory effect.

6. The deployable annular propeller according to claim 4, characterized in that: When the blade (2) is bent into a ring shape, the inner ring contour of the ring shape is used as the inner edge, and the bone rod (22) is inserted into the blade (21) along the inner edge.

7. The deployable annular propeller according to claim 4, characterized in that: The locking portion (3) comprises: Two telescopic mechanisms (31) are symmetrically arranged in the slot (101) and are respectively aligned with two blade surfaces of the tip (202); Two clamping blocks (32) are respectively connected to the two telescopic mechanisms (31) and move toward or away from the blade surface of the tip (202) under the drive of the telescopic mechanisms (31); The two clamping blocks (32) simultaneously move toward each other and clamp the tip (202), or the two clamping blocks (32) simultaneously move away from each other and release the tip (202).

8. The deployable annular propeller according to claim 7, characterized in that: The locking portion (3) further comprises: A cable mechanism (33) is arranged at the bottom of the slot (101); A through hole (203) is provided in the blade (21), one end of the through hole (203) is connected to the outside, and the other end of the through hole (203) extends toward the free end of the bone rod (22) and exposes the end of the bone rod (22); The cable mechanism (33) is connected to the end of the bone rod (22) via a cable passing through the through hole (203); the cable mechanism (33) pulls the bone rod (22) via the cable and causes the bone rod (22) to deform under force, or the cable mechanism (33) releases the cable.

9. The deployable annular propeller according to claim 1, characterized in that: Taking the direction of the annular propeller toward the downstream as the positive direction, the root (201) is arranged at a portion of the hub (1) close to the downstream, and the tip (202) is bent into a ring shape toward a portion of the hub (1) close to the upstream.

10. A cross-domain aircraft, characterized in that: A deployable annular propeller according to any one of claims 1 to 9; When the cross-domain vehicle is sailing underwater, the blade (2) is in a first state and is bent into a ring shape, and the tip (202) is connected to the locking portion (3); When the cross-domain aircraft is sailing in the air, the locking portion (3) releases the tip (202), and the blade (2) switches to the second form.

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