Rotary wing aircraft

Abstract

To provide a rotary wing aircraft having improved safety with a simple structure.SOLUTION: This rotary wing aircraft 1 has a body surrounded by a cage side 3A, and includes an aerodynamic parts side 3A composed of a plate-shaped body inclined to the outside of the cage side 3A, and arranged so as to surround an upper surface, in the edge of the upper surface for constituting the cage side 4A.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a rotorcraft such as a drone having multiple rotors. [Background technology]

[0002] In recent years, various drones have become commercially available, and Patent Document 1 discloses a drone equipped with a parachute and airbags to reduce the risk of falling accidents. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 2018-193055 Summary of the Invention [Problem to be solved by the invention]

[0004] However, when using parachutes or airbags as described above, not only is it necessary to have a means for determining the timing of their deployment, but there is also the issue of the risk that the means or the parachute may not function properly during a fall.

[0005] Furthermore, even if the above-mentioned means and the parachute etc. operate normally when the drone falls, there is a problem in that the parachute may catch the wind during the fall, causing the entire drone to be blown around, creating a risk that the drone may land in an unexpected location.

[0006] Furthermore, since the parachutes and the like are deformable, there is a risk that the expected effect may not be fully achieved when in use, and there is also the problem that they are bulky when folded up when not in use.

[0007] The present invention has been made to solve these problems, and has an object to provide a rotorcraft with improved safety through a simple configuration. [Means for solving the problem]

[0008] In order to solve the above problem, the present invention provides a rotary-wing aircraft whose main body is surrounded by a cage, and which is provided with a plate-shaped body at the edge of the upper surface that constitutes the cage, which is inclined outward from the cage and is arranged to surround the upper surface. [Effects of the Invention]

[0009] According to the present invention, it is possible to provide a rotorcraft with improved safety through a simple configuration. [Brief explanation of the drawings]

[0010] [Figure 1] 1 is a perspective view showing the configuration of a drone 1 according to a first embodiment of the present invention. [Figure 2] FIG. 10 is a perspective view showing the configuration of a drone 10 according to a second embodiment of the present invention. [Figure 3] FIG. 10 is a perspective view showing the configuration of a drone 20 according to a third embodiment of the present invention. [Figure 4] FIG. 10 is a perspective view showing the configuration of a drone 30 according to a fourth embodiment of the present invention. [Figure 5] FIG. 10 is a perspective view showing the configuration of a drone 40 according to a fifth embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0011] Drones with multiple rotors generally have the characteristic that when they fall, the rotors (propellers) rotate due to the vertical upward airflow, and they receive a force that restores their posture to prevent them from flipping over, causing them to fall to the ground while maintaining their posture.

[0012] However, if a cage is added to protect the propeller in order to reduce the risk of hands being cut by the rotating propeller as a measure to improve personal safety, the restoring force will be lost when the drone falls, causing it to tip over and hit the ground.

[0013] Therefore, it was demonstrated that if an aerodynamic part consisting of a plate-shaped body such as the one shown below is attached to the edge of the upper surface of the cage, the restoring force is restored, allowing the cage to fall without tipping over, and the air resistance experienced by the aerodynamic part reduces the falling speed.

[0014] Therefore, the drone according to the embodiment of the present invention, which has been verified as described above, will be described in detail below with reference to the drawings. Note that the same reference numerals in the drawings indicate the same or corresponding parts.

[0015] [Embodiment 1] Fig. 1 is a perspective view showing the configuration of a drone 1 according to a first embodiment of the present invention. As shown in Fig. 1, the drone 1 includes a main body 2 having four rotors (propellers), a cage 3A that is a rectangular parallelepiped with no bottom and has each face made of a lattice net and is provided to surround the main body 2 in order to protect the rotation of the propellers and reduce the risk of cutting a person's hands or other parts with the propellers rotating at high speed, and an aerodynamic part 4A made of a plate-like body that is inclined outward from the cage 3A at the edge of the top surface that constitutes the cage 3A and is provided to surround the top surface.

[0016] The material of the aerodynamic part 4A may be plastic, metal such as aluminum alloy, or paper. The inclination is, for example, an angle of 45 degrees from the upper surface to the vertical direction, but is not limited to this.

[0017] The following describes the effects of the drone 1 configured as described above. When the drone 1 falls due to a malfunction or other reason, the airflow flowing upward along the side of the cage 3A strikes the aerodynamic part 4A and is redirected outward from the drone body, creating a vortex that acts as a force to restore the drone's posture, maintaining it horizontal and reducing the speed of its fall.

[0018] More specifically, the restoring force causes the falling aircraft to perturb around the horizontal attitude without tipping over, or to converge the perturbation as it falls.

[0019] At this time, the drone 1 is not affected by wind because the main body 2 is enclosed in the lattice cage 3A as described above, which reduces the risk of the drone landing in an unexpected location when it falls.

[0020] Furthermore, since the drone 1 can be crashed into the ground while being held in a horizontal position, damage to the main body 2 can be reduced by deforming the mesh that forms the side of the cage 3A into an accordion-like shape to absorb the impact received during the collision.

[0021] According to the drone 1 of embodiment 1 of the present invention as described above, by being equipped with a simple configuration of aerodynamic part 4A, it is possible to maintain a stable posture without tipping over when falling, while reducing the falling speed compared to when in free fall.

[0022] Here, since the aerodynamic part 4A is not operated using a power source or actuator, etc., the above-mentioned effect can be obtained even if an unexpected situation occurs, such as the drone 1 losing all of its power source or a built-in actuator malfunctioning, thereby further increasing the safety of the drone 1.

[0023] Furthermore, with the drone 1 according to this embodiment 1, the above-mentioned effect of the aerodynamic parts 4A can be obtained from the moment the drone enters a falling state, and it is also possible to avoid being blown around by the wind, thereby reducing the risk of the drone landing in an unexpected location and further increasing safety.

[0024] Furthermore, according to the drone 1 of this embodiment 1, unlike the above-mentioned parachutes and the like, the aerodynamic parts 4A do not deform, so there is an advantage that the expected action and effect can be reliably obtained when the drone falls, and there is no problem of it being bulky when stored when not in use.

[0025] Although the above description has been given as an example of a case where the cage 3A has a rectangular parallelepiped shape without a bottom surface, the same effect can be obtained even if the cage 3A has another shape that surrounds the main body 2.

[0026] In addition, the lattice mesh that forms each surface of the cage 3A can be a square mesh, a hexagonal mesh, etc., but if a hexagonal mesh is used, the overall weight of the drone 1 can be reduced compared to the case of a square mesh.

[0027] [Embodiment 2] Fig. 2 is a perspective view showing the configuration of drone 10 according to embodiment 2 of the present invention. Drone 10 according to embodiment 2 of the present invention has a similar configuration to drone 1 according to embodiment 1 above, and achieves similar effects, but differs in that it further includes a membrane 5 provided on the side of cage 3A so as to be connected to aerodynamic part 4A, as shown in Fig. 2. In the following, a description of parts common to drone 1 according to embodiment 1 will be omitted.

[0028] According to the drone 10 of the second embodiment, the membrane 5 doubles the restoring force that prevents the drone from tipping over when dropped, allowing it to return to its original position even when tilted at a greater angle. This is because the membrane 5 serves to smooth the upward airflow flowing into the aerodynamic part 4A, smoothing the shape of the vortex generated by the aerodynamic part 4A, thereby increasing the efficiency with which the restoring force is generated. This further stabilizes the attitude of the drone 10, further improving the safety.

[0029] Regarding the height (vertical width) of the membrane 5, if it is too small, the above-mentioned effect will not be obtained, and if it is too large, there is a risk that the entire drone 10 will be easily blown around by crosswinds.

[0030] [Embodiment 3] Fig. 3 is a perspective view showing the configuration of drone 20 according to embodiment 3 of the present invention. Drone 20 according to embodiment 3 of the present invention has a similar configuration to drone 10 according to embodiment 2 above, and achieves similar effects, but differs in that main body 2 is surrounded by cage 3B made of a truss structure instead of lattice-shaped cage 3A, as shown in Fig. 3. In the following, a description of parts common to drone 10 according to embodiment 2 will be omitted.

[0031] The cage 3B is made of a truss structure made of, for example, plastic, carbon fiber composite material, aluminum alloy, or the like, which allows for increased strength and higher rigidity while reducing the weight.

[0032] [Embodiment 4] Fig. 4 is a perspective view showing the configuration of a drone 30 according to a fourth embodiment of the present invention. The drone 30 according to the fourth embodiment of the present invention has a similar configuration to the drone 20 according to the third embodiment described above, and achieves similar effects, but differs in that, as shown in Fig. 4, the drone 30 has an aerodynamic part 4B in which the upper end of a plate-like body has a sawtooth shape (chevron shape) instead of the aerodynamic part 4A described above. In the following, a description of the parts common to the drone 20 according to the third embodiment will be omitted.

[0033] When drone 30 falls, it receives a vertically upward wind that diffuses from the side of cage 3B through aerodynamic part 4B into the open space. However, during this diffusion, large vortices may be generated, or vortices of uneven size may be generated in the front, back, left, and right directions, resulting in variations in the magnitude of the force that restores the posture around main body 2.

[0034] Therefore, the aerodynamic part 4B has a chevron shape at the upper end, which creates a point that breaks down the vortices that act to restore the drone's posture into smaller pieces. By uniformly and stably generating small, uniformly sized vortices from this upper end, a uniform restoring force is generated, allowing the drone 30 to fall without much shaking or tipping over.

[0035] It goes without saying that the same effect can be obtained in the drones 1 and 10 according to the first and second embodiments by providing an aerodynamic part 4B having a chevron-shaped upper end as described above instead of the aerodynamic part 4A.

[0036] [Embodiment 5] The drones 10, 20, and 30 according to the above-mentioned embodiments 2 to 4 all have a membrane 5 on the side of the cage 3A or 3B, but since the above-mentioned posture restoring force can also be generated by a configuration other than the membrane 5, this configuration will be described below.

[0037] Fig. 5 is a perspective view showing the configuration of a drone 40 according to a fifth embodiment of the present invention. As shown in Fig. 5, the drone 40 according to the fifth embodiment of the present invention has a configuration similar to that of the drone 1 according to the first embodiment, and achieves similar effects, but differs in that it includes a cage 3C instead of the cage 3A, the cage 3C having sides formed of a plurality of plate-like frames 6 arranged at predetermined intervals in the vertical direction and each surrounding the main body on one plane. In the following, a description of parts common to the drone 1 according to the first embodiment will be omitted.

[0038] According to the cage 3C described above, the sides are made of layered plate-like frames 6, which allows air to flow easily in the horizontal direction but not in the vertical direction. This creates air resistance in the vertical direction, reducing the falling speed and generating a posture restoring force.

[0039] The above-described effects can be obtained whether the upper surface of the cage 3C in this embodiment has a grid or hexagonal mesh or a truss structure.

[0040] In the above, drones 1, 10, 20, 30, and 40 with four rotors have been used as examples of embodiments of the present invention, but the present invention is not limited to these, and similar effects can be obtained by applying the invention to rotorcraft with one or more rotors other than four. [Explanation of symbols]

[0041] 1,10,20,30,40 drone, 2 main body, 3A,3B,3C cage, 4A,4B aerodynamic parts, 5 membrane, 6 plate-shaped frame.

Claims

1. A rotorcraft having a body surrounded by a cage, A rotary-wing aircraft comprising a plate-shaped body at the edge of the upper surface of the cage, the plate-shaped body inclining outward from the cage and surrounding the upper surface.

2. The rotorcraft according to claim 1 , further comprising a membrane provided on a side surface of the cage so as to be connected to the plate-like body.

3. The rotary wing aircraft according to claim 1 , wherein an upper end of the plate-like body is saw-tooth shaped.

4. The rotorcraft according to claim 1 , wherein the cage is a rectangular parallelepiped with no bottom, each face of which is formed of a lattice-like mesh.

5. The rotorcraft of claim 1 , wherein the cage comprises a truss structure.

6. The rotorcraft according to claim 1 , wherein the side surfaces of the cage are configured by a plurality of plate-like frames provided at predetermined intervals in the vertical direction, each of the plate-like frames surrounding the main body in one plane.

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