Flight vehicle and flight vehicle guard

Abstract

This flight vehicle capable of flight comprises: a vehicle body having a propeller; a plurality of shafts that are connected to the vehicle body; a guard frame that is connected to the plurality of shafts and is disposed on the outer side of the vehicle body in a plan view of the flight vehicle; and a shock-absorbing mechanism that absorbs shock load inputted to the guard frame. This flight vehicle guard mounted to a vehicle body having a propeller comprises: a plurality of shafts that are connected to the vehicle body; a guard frame that is connected to the plurality of shafts; and a shock-absorbing mechanism that absorbs shock load inputted to the guard frame.

Description

Aircraft and aircraft guards

[0001] One aspect of the present invention relates to an air vehicle such as a drone and a guard for the air vehicle.

[0002] Patent Document 1 describes a flying vehicle with rotors (propellers) arranged on multiple radially arranged arms. This flying vehicle is equipped with a guard frame connecting the multiple arms to prevent contact between the rotors (propellers) and obstacles.

[0003] JP 2011-046355 A

[0004] Incidentally, aircraft equipped with guard frames, such as the aircraft described in Patent Document 1, collide with obstacles such as walls at the guard frames. When the guard frames collide with the obstacle, the guard frames are deformed by the impact load input from the obstacle. This, combined with the propulsion force (inertial force) of the aircraft toward the obstacle, increases the deformation of the guard frames. The deformed guard frames attempt to return to their original shape due to a restoring force, making the aircraft prone to bouncing off the obstacle and losing its balance. In this case, if the impact load input to the guard frames is large and the guard frames are deformed significantly, the restoring force of the guard frames also increases, making the aircraft prone to bouncing off and falling.

[0005] Therefore, one aspect of the present invention aims to provide an aircraft and an aircraft guard that can prevent the aircraft from falling in the event of a collision.

[0006] [1] An aircraft according to one aspect of the present invention is a flyable aircraft comprising: a fuselage having a propeller; a plurality of shafts (long, thin, linear members) connected to the fuselage; a guard frame connected to the plurality of shafts and positioned outside the fuselage in a planar view of the aircraft; and an impact absorbing mechanism that absorbs impact loads input to the guard frame.

[0007] In this aircraft, the guard frame is located outside the aircraft when viewed from above, so when the aircraft collides with an obstacle such as a wall at the guard frame, the guard frame is deformed by the impact load from the obstacle. However, the impact absorbing mechanism absorbs the impact load input to the guard frame, reducing the deformation of the guard frame. This makes it possible to prevent the aircraft from falling during a collision.

[0008] [2] In the aircraft described in [1], the shock absorbing mechanism may include a spring. In this aircraft, the shock absorbing mechanism includes a spring, which allows the shock load input to the guard frame to be appropriately absorbed.

[0009] [3] In the aircraft described in [1] or [2], the shock absorbing mechanism may have an elastic member that is elastically deformable in the expansion and contraction direction. In this aircraft, the shock absorbing mechanism has an elastic member that is elastically deformable in the expansion and contraction direction, so that the impact load input to the guard frame can be appropriately absorbed.

[0010] [4] In the aircraft described in [1] or [2], the shock absorbing mechanism may have a torsion member that is elastically deformable in a torsional direction. In this aircraft, the shock absorbing mechanism has a torsion member that is elastically deformable in a torsional direction, so that the shock load input to the guard frame can be appropriately absorbed.

[0011] [5] In the aircraft according to any one of [1] to [4], the shock absorbing mechanism may have a damping force that damps vibrations of the guard frames. In this aircraft, the shock absorbing mechanism has a damping force that damps vibrations of the guard frames, making it easier to return the aircraft to its original position after being displaced by a collision with an obstacle.

[0012] [6] In the aircraft described in any one of [1] to [5], the shock absorbing mechanism may be provided on at least one of the shafts. In this aircraft, when the guard frame collides with an obstacle, the shock absorbing mechanism can absorb the thrust (inertial force) of the aircraft toward the obstacle, thereby preventing excessive deformation of the guard frame.

[0013] [7] In the aircraft described in any one of [1] to [6], the aircraft may have a central section and a plurality of arms extending from the central section and having propellers attached thereto, each of the plurality of shafts being connected to one of the arms, and the shock absorbing mechanism may be provided on the arms. In this aircraft, by providing the shock absorbing mechanism on the arms, when the guard frame collides with an obstacle, the thrust force of the central section of the aircraft toward the obstacle can be absorbed, thereby preventing excessive deformation of the guard frame.

[0014] [8] In the aircraft described in any one of [1] to [6], the aircraft may have a central section and a plurality of arms extending from the central section and having propellers attached thereto, each of the plurality of shafts connected to one of the arms, and the shock absorbing mechanism may be provided at a connection between the arm and the shaft. In this aircraft, the shock absorbing mechanism provided at the connection between the arm and the shaft can absorb the propulsion force of the aircraft toward the obstacle when the guard frame collides with the obstacle, thereby preventing excessive deformation of the guard frame.

[0015] [9] The aircraft described in any one of [1] to [8] may further include a diagonal brace connected to at least one of the shafts and the guard frame, and the shock absorbing mechanism may be provided in the diagonal brace. By providing the diagonal brace connected to at least one of the shafts and the guard frame, the rigidity of the guard frame can be increased and the impact load input to the guard frame can be distributed to the diagonal brace. Furthermore, by providing the shock absorbing mechanism in the diagonal brace, the impact load distributed from the guard frame to the diagonal brace can be absorbed. This reduces the deformation of the guard frame and reduces the rebound when colliding with an obstacle, thereby preventing the aircraft from falling during the collision.

[0016]

[10] In the aircraft described in any one of [1] to [9], the guard frame may be disposed only above the aircraft's center of gravity in the vertical direction. In this aircraft, when the guard frame collides with an obstacle such as a wall, the propeller's lift causes the aircraft to rotate in a direction tilting forward relative to the obstacle. Meanwhile, because the guard frame is disposed only above the aircraft's center of gravity in the vertical direction, the aircraft's thrust causes the aircraft to rotate in a direction tilting backward relative to the obstacle. Because these rotations are in opposite directions, they cancel each other out. This not only absorbs the impact load input to the guard frame via the shock absorbing mechanism, but also minimizes rotation upon collision with an obstacle, further preventing the aircraft from falling upon impact. Furthermore, because the guard frame is disposed only above the aircraft's center of gravity in the vertical direction, the guard frame is less likely to obstruct the aircraft's view of the surroundings. This ensures a clear view of the surroundings. In addition, the guard frame can be made lighter than when it is positioned vertically below the center of gravity of the aircraft, thereby increasing flight time.

[0017]

[11] In the aircraft described in

[10] , the guard frame may be positioned above the propeller in the vertical direction of the aircraft. In this aircraft, the guard frame is positioned above the propeller in the vertical direction of the aircraft, making it easier to position the guard frame only above the center of gravity of the aircraft in the vertical direction. This also makes it possible to further ensure surrounding visibility while further reducing the risk of the aircraft falling in the event of a collision.

[0018]

[12] The flying vehicle described in

[10] or

[11] may be configured to propel itself while tilting forward at an inclination angle, and the guard frame may be disposed only vertically above the position of the center of gravity of the flying vehicle when tilted at the inclination angle. In this flying vehicle, when configured to propel itself while tilting forward at an inclination angle, by disposing the guard frame only vertically above the position of the center of gravity of the flying vehicle when tilted at the inclination angle, it is possible to further ensure visibility of the surroundings while further suppressing a fall in the event of a collision.

[0019]

[13] In the flying vehicle described in any one of

[10] to

[12] , the guard frame may be positioned only vertically above the position of the center of gravity of the flying vehicle when the flying vehicle is tilted 3°. Flying vehicles often propel while leaning forward in the direction of flight, and the angle of forward tilt of the flying vehicle at this time is often within 3°. Therefore, by positioning the guard frame only vertically above the position of the center of gravity of the flying vehicle when the flying vehicle is tilted 3°, it is possible to further ensure surrounding visibility while further suppressing a fall in the event of a collision.

[0020]

[14] In the aircraft described in any one of [1] to

[13] , the guard frame may include a first guard frame and a second guard frame arranged below the first guard frame in the vertical direction of the aircraft, and the second guard frame may be arranged inside the first guard frame in a plan view of the aircraft. In this aircraft, the guard frames include the first guard frame and the second guard frame arranged above and below each other, thereby increasing the rigidity of the guard frame and the multiple shafts. Moreover, the second guard frame, which is arranged below the first guard frame in the vertical direction of the aircraft, is arranged inside the first guard frame in a plan view of the aircraft, thereby preventing the second guard frame from colliding with the obstacle before the first guard frame when the aircraft collides with an obstacle. This prevents the second guard frame from interfering with the aircraft's rotation during a collision, thereby preventing the aircraft's attitude from becoming unstable.

[0021]

[15] An aircraft guard according to one aspect of the present invention is an aircraft guard attached to an airframe having a propeller, and includes a plurality of shafts connected to the airframe, a guard frame connected to the plurality of shafts, and an impact absorbing mechanism that absorbs impact loads input to the guard frame.

[0022] When an aircraft equipped with this aircraft guard collides with an obstacle such as a wall at the guard frame, the guard frame is deformed by the impact load from the obstacle. However, the impact absorbing mechanism absorbs the impact load input to the guard frame, reducing the deformation of the guard frame. This prevents the aircraft from falling during the collision.

[0023]

[16] In the aircraft guard according to

[15] , the impact absorbing mechanism may have a spring. In this aircraft guard, the impact absorbing mechanism has a spring, which makes it possible to absorb an impact load input to the guard frame.

[0024]

[17] In the aircraft guard described in

[15] or

[16] , the guard frame may be positioned only above the aircraft-side tips of the shafts in the vertical direction of the aircraft guard. When an aircraft equipped with this aircraft guard collides with an obstacle such as a wall at the guard frame, the aircraft attempts to rotate in a direction tilting forward relative to the obstacle due to the lift of the propeller. Meanwhile, because the guard frame is positioned only above the aircraft-side tips of the shafts in the vertical direction of the aircraft guard, the aircraft attempts to rotate in a direction tilting backward relative to the obstacle due to the aircraft's propulsion force. Because these rotations are in opposite directions, they cancel each other out. This not only absorbs the impact load input to the guard frame via the shock absorbing mechanism, but also minimizes rotation upon collision with an obstacle, thereby further preventing the aircraft from falling upon impact. Furthermore, because the guard frame is positioned only above the aircraft-side tips of the shafts in the vertical direction of the aircraft guard, the aircraft equipped with the aircraft guard is prevented from obstructing the surrounding field of view due to the guard frame. This ensures a good view of the surroundings.

[0025]

[18] In the aircraft guard described in any one of

[15] to

[17] , the guard frame may include a first guard frame and a second guard frame disposed below the first guard frame, and the second guard frame may be disposed inside the first guard frame in a plan view of the aircraft guard. In this aircraft guard, the first and second guard frames are disposed above and below the first guard frame, thereby increasing the rigidity of the aircraft guard. Furthermore, the second guard frame, which is disposed below the first guard frame, is disposed inside the first guard frame in a plan view of the aircraft guard. This prevents the second guard frame from colliding with an obstacle before the first guard frame when the aircraft to which the aircraft guard is attached collides with the obstacle. This prevents the second guard frame from hindering the aircraft's rotation during a collision, thereby preventing the aircraft's attitude from becoming unstable.

[0026] According to one aspect of the present invention, it is possible to prevent a device from falling in the event of a collision.

[0027] 1. A perspective view of a flying body according to a first embodiment. 2. A front view of a flying body according to the first embodiment. 3. A plan view of a flying body according to the first embodiment. 4. A schematic view showing an example of a shock absorbing mechanism. 5. A schematic view showing another example of a shock absorbing mechanism. 6. A front view of a flying body flying with a forward tilt. 7. A front view of a flying body flying with a forward tilt and collides with an obstacle. 8. A perspective view of a flying body according to a second embodiment. 9. A plan view of a flying body according to the second embodiment. 10. A perspective view of a flying body according to a third embodiment. 11. A plan view of a flying body according to the third embodiment. 12. A plan view of a flying body according to the third embodiment. 13. A perspective view of a flying body according to a fourth embodiment. 14. A plan view of a flying body according to the fourth embodiment. 15. A plan view of a flying body according to the fourth embodiment. 16. A perspective view of a flying body according to the fourth embodiment. 17. A plan view of a flying body according to the fourth embodiment. 18. A perspective view of a flying body according to the fifth embodiment. 19. A plan view of a flying body according to the fifth embodiment.

[0028] Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings. In the following description, the same or equivalent elements will be designated by the same reference numerals, and redundant description will be omitted.

[0029] [First Embodiment] An aircraft according to the first embodiment will be described with reference to FIGS. 1 to 3. FIG. 1 is a perspective view of the aircraft 1 according to the first embodiment. FIG. 2 is a front view of the aircraft 1 according to the first embodiment. FIG. 3 is a plan view of the aircraft 1 according to the first embodiment. As shown in FIGS. 1 to 3, the aircraft 1 according to the first embodiment is a flyable aircraft, such as a drone. The aircraft 1 according to the first embodiment includes an airframe 2 and an aircraft guard 3. The up-down direction D1 of the aircraft 1 is the up-down direction of the aircraft 1 placed on a horizontal surface or the up-down direction of the aircraft 1 while hovering. The up-down direction of the airframe 2 and the aircraft guard 3 is the same as the up-down direction D1 of the aircraft 1. The up-down direction in the up-down direction D1 of the aircraft 1 is the up-down direction in FIG. 2. A line passing through the center of the aircraft 1 and extending in the up-down direction D1 of the aircraft 1 is referred to as a reference line L.

[0030] The airframe 2 is the part that forms the main body of the aircraft 1. The airframe 2 has a central section 4, multiple arm sections 5, and multiple propellers 6. The airframe 2 also includes, for example, a transceiver (not shown) that transmits and receives wireless signals to and from an external device, a control device (not shown) for flying the aircraft 1, a motor (not shown) for rotating the propellers 6, and a battery (not shown) for supplying power to the control device, motor, etc.

[0031] The central section 4 is a section located in the center of the aircraft 1. The central section 4 is equipped with, for example, a transmitter / receiver, a control device, a battery, etc. An observation device 7 such as a camera for observing the surroundings of the aircraft 1 is detachably attached to the central section 4. The observation device 7 is, for example, a separate component from the aircraft 1 and is detachably attached to the bottom surface of the central section 4. Note that the observation device 7 does not have to be detachably attached to the central section 4, but may instead be an internal component of the aircraft 1 that is mounted on the bottom of the central section 4.

[0032] The multiple arm portions 5 extend in different directions from the central portion 4. The multiple arm portions 5 are, for example, arranged at equal angles around the reference line L. Each of the multiple arm portions 5 is equipped with, for example, a motor. The number of arm portions 5 is not particularly limited, but in this embodiment, for example, there are four arm portions 5.

[0033] The multiple propellers 6 rotate to fly the aircraft 1. Each of the multiple propellers 6 is rotatably attached to each of the multiple arm units 5. In other words, one propeller 6 is attached to one arm unit 5. The multiple propellers 6 are arranged on the same circumference centered on the reference line L. Each of the multiple propellers 6 is rotated by, for example, a motor mounted on each of the multiple propellers 6.

[0034] The aircraft guard 3 protects the aircraft 2. In other words, the aircraft guard 3 prevents the aircraft 2, particularly the propeller 6, from colliding with an obstacle such as a wall when the aircraft 1 collides with the obstacle. The aircraft guard 3 includes a plurality of shafts 8, a guard frame 9, and an impact absorbing mechanism 20.

[0035] Each of the multiple shafts 8 is a portion that supports the guard frame 9 relative to the airframe 2. Each of the multiple shafts 8 is connected to the airframe 2 and the guard frame 9. Each of the multiple shafts 8 is, for example, detachably connected to the airframe 2. The detachable connection of each of the multiple shafts 8 to the airframe 2 can be achieved by, for example, screwing, fitting, engagement, etc. Note that each of the multiple shafts 8 may be non-detachably connected to the airframe 2. Each of the multiple shafts 8 is, for example, non-detachably connected to the guard frame 9. The non-detachable connection of each of the multiple shafts 8 to the guard frame 9 can be achieved by, for example, integral molding, adhesive bonding, etc. Note that the guard frame 9 may be detachably connected to each of the multiple shafts 8.

[0036] Each of the multiple shafts 8 is connected to one of the multiple arm units 5 of the machine body 2. More specifically, two or more shafts 8 are connected to each of the multiple arm units 5. The number of shafts 8 connected to one arm unit 5 is not particularly limited, but in this embodiment, two shafts are used as an example. The portion where the shaft 8 and the arm unit 5 are connected is called a connection portion 10.

[0037] In a plan view of the aircraft 1, each of the multiple shafts 8 extends in a direction away from the center of the aircraft 2, from its tip on the fuselage 2 side to its tip on the guard frame 9 side. In other words, in a plan view of the aircraft 1, each of the multiple shafts 8 does not have a portion that does not extend in a direction away from the center of the aircraft 2, and does not have a portion that extends only in the vertical direction D1 of the aircraft 1. A plan view of the aircraft 1 refers to a view from a direction along the reference line L, that is, a direction along the vertical direction D1 of the aircraft 1. A plan view of the aircraft guard 3 is the same as a plan view of the aircraft 1. The center of the aircraft 2 is the center of the aircraft 1 and is on the reference line L.

[0038] Each of the multiple shafts 8 is formed as a single line from its tip on the aircraft body 2 side to its tip on the guard frame 9 side. In other words, each of the multiple shafts 8 extends from its tip on the aircraft body 2 side to its tip on the guard frame 9 side without branching into multiple shafts.

[0039] Each of the multiple shafts 8 is formed to bend. Specifically, each of the multiple shafts 8 has a horizontal portion 8a and an inclined portion 8b. The horizontal portion 8a is connected to the arm portion 5 of the aircraft 2. The horizontal portion 8a is disposed below the propeller 6 in the up-down direction D1 of the aircraft 1. The horizontal portion 8a extends from the arm portion 5 toward the lateral direction of the aircraft 1 so as to move away from the center of the aircraft 2. The lateral direction of the aircraft 1 is a direction perpendicular to the reference line L. The inclined portion 8b is connected to the guard frame 9. The inclined portion 8b is bent and connected to the horizontal portion 8a and disposed to the side of the propeller 6. The inclined portion 8b extends from the tip of the horizontal portion 8a in a direction inclined with respect to the reference line L so as to move away from the center of the aircraft 2. In other words, the inclined portion 8b extends from the tip of the horizontal portion 8a to the tip of the guard frame 9 while being inclined in the lateral direction of the aircraft 1 and in the up-down direction D1 of the aircraft 1. As a result, each of the multiple shafts 8 has a curved shape that follows the propeller 6. However, each of the multiple shafts 8 may have any curved shape as long as it does not come into contact with the airframe 2.

[0040] The guard frame 9 is a part that protects the airframe 2. In other words, when the air vehicle 1 collides with an obstacle, the guard frame 9 hits the obstacle before the airframe 2, thereby preventing the airframe 2 from colliding with the obstacle. In order to protect the airframe 2, the guard frame 9 is arranged outside the airframe 2 in a plan view of the airframe 1.

[0041] The guard frame 9 is formed in a ring shape that surrounds the airframe 2 in a plan view of the aircraft 1. In this embodiment, the multiple propellers 6 are arranged on the same circumference centered on the reference line L, and therefore the guard frame 9 is formed in a perfect ring shape. However, in cases where the multiple propellers 6 are arranged in an elliptical shape, or where the airframe 2 extends long in either direction, the guard frame 9 may be formed in an elliptical ring shape that follows the multiple propellers 6.

[0042] The guard frame 9 is positioned only above the center of gravity G of the aircraft 1 in the vertical direction D1 of the aircraft 1. In other words, the guard frame 9 is supported by the multiple shafts 8 so that it is positioned only above the center of gravity G of the aircraft 1 in the vertical direction D1 of the aircraft 1. Furthermore, the guard frame 9 is positioned only above the tips of the multiple shafts 8 on the fuselage 2 side in the vertical direction of the aircraft guard 3. Note that the guard frame 9 may be positioned above the multiple propellers 6 in the vertical direction D1 of the aircraft 1, or may be positioned only above the multiple propellers 6 in the vertical direction D1 of the aircraft 1.

[0043] The center of gravity G of the aircraft 1 is the center of gravity of the aircraft 1 including the airframe 2 and the aircraft guard 3. For example, if the observation device 7 is a separate component from the aircraft 1 and the separate aircraft 1 is detachably attached to the airframe 2, the center of gravity G of the aircraft 1 is the center of gravity of the aircraft 1 excluding the observation device 7. Furthermore, if the observation device 7 is an internal component of the aircraft 1 and is pre-installed on the airframe 2, the center of gravity G of the aircraft 1 is the center of gravity of the aircraft 1 including the observation device 7.

[0044] The shock absorbing mechanism 20 absorbs the impact load input to the guard frame 9. When the guard frame 9 collides with an obstacle, the guard frame 9 is deformed by the impact load input from the obstacle. This, combined with the propulsion force (inertial force) of the aircraft 2 toward the obstacle, increases the deformation of the guard frame 9. The deformed guard frame 9 attempts to return to its original shape due to a restoring force, making the aircraft 1 prone to bouncing off the obstacle and losing its posture. At this time, if the impact load input to the guard frame 9 is large and the deformation of the guard frame 9 is large, the restoring force of the guard frame also increases, making the aircraft 1 prone to bouncing off and falling.

[0045] Therefore, the impact absorbing mechanism 20 absorbs the impact load input to the guard frame 9, thereby reducing deformation of the guard frame 9 and preventing it from falling during a collision. The impact absorbing mechanism 20 may be, for example, a mechanism having a spring. In the drawings, the impact absorbing mechanism 20 is indicated by sand-like (dot-like) hatching. Note that the impact absorbing mechanism 20 may be a mechanism that not only absorbs the impact load input to the guard frame 9 but also obtains a damping force that attenuates vibration of the guard frame 9. The type, position, number, etc. of the impact absorbing mechanism 20 are not particularly limited as long as it can absorb the impact load input to the guard frame 9.

[0046] For example, the shock absorbing mechanism 20 may be a mechanism having an elastic member that is elastically deformable in the expansion and contraction direction, or a mechanism having a torsion member that is elastically deformable in the torsion direction. The elastic member and the torsion member may be a type of spring. Examples of the elastic member that can be used include a gas spring, an oil spring, and a compression coil spring. Note that the gas spring and the oil spring can not only absorb the impact load input to the guard frame 9, but also damp vibrations of the guard frame 9. Examples of the torsion member that can be used include a torsion spring.

[0047] When the shock absorbing mechanism 20 is a mechanism having an expandable member, the expandable member is arranged to absorb the impact load input to the guard frame 9, for example, by being compressed. Furthermore, when the shock absorbing mechanism 20 is a mechanism having an expandable member, the shock absorbing mechanism 20 may have an extension restriction mechanism (not shown) that restricts deformation of the expandable member in the extension direction. Cylinders used in gas springs and oil springs also function as extension restriction mechanisms that restrict deformation of the expandable member 21 in the extension direction.

[0048] The shock absorbing mechanism 20 is provided, for example, on at least one of the multiple arm portions 5. In this case, the shock absorbing mechanism 20 is preferably provided on the arm portion 5 on the side opposite the central portion 4 from the propeller 6. The shock absorbing mechanism 20 is also provided, for example, on at least one of the multiple shafts 8. The shock absorbing mechanism 20 is also provided, for example, on at least one of the connection portions 10 between the arm portion 5 and the shaft 8. The drawings show a configuration in which the shock absorbing mechanism 20 is provided on all of the arm portions 5, all of the shafts 8, and all of the connection portions 10. However, it is sufficient that the shock absorbing mechanism 20 is provided on at least one of these. For example, the shock absorbing mechanism 20 may be provided only on the multiple arm portions, only on the multiple shafts 8, or only on the multiple connection portions 10. In addition, the shock absorbing mechanism 20 may be provided only on the arm section 5 among the multiple arm sections 5 that is located at the front in the flight direction of the aircraft 1, or may be provided only on the shaft 8 among the multiple shafts 8 that is located at the front in the flight direction of the aircraft 1, or may be provided only on the connection section 10 among the multiple connection sections 10 that is located at the front in the flight direction of the aircraft 1.

[0049] Fig. 4 is a schematic diagram showing an example of a shock absorbing mechanism. The shock absorbing mechanism 20a shown in Fig. 4 is a shock absorbing mechanism 20 having an expandable member 21 that is elastically deformable in the expansion / contraction direction D5, such as a gas spring, oil spring, or compression coil spring. In the shock absorbing mechanism 20a, one end of the expandable member 21 is connected to a first member 22, and the other end of the expandable member 21 is connected to a second member 23. The shock absorbing mechanism 20a absorbs an impact load input to the first member 22 and the second member 23 by moving the first member 22 and the second member 23 relatively in the expansion / contraction direction D5 of the expandable member 21.

[0050] When the shock absorbing mechanism 20a is provided on the arm portion 5, the first member 22 and the second member 23 are two divided bodies formed by dividing the arm portion 5. In other words, the first member 22 is one divided body of the arm portion 5, and the second member 23 is the other divided body of the arm portion 5. The shock absorbing mechanism 20a absorbs the propulsive force toward an obstacle in the central portion 4 of the aircraft 2 by relatively moving the first member 22 and the second member 23 in the extension / contraction direction D5 of the extendable member 21, and also absorbs the impact load transmitted from the guard frame 9 to the arm portion 5 via the shaft 8. In this way, the impact load input to the guard frame 9 is absorbed.

[0051] When the shock absorbing mechanism 20a is provided on the shaft 8, the first member 22 and the second member 23 are two divided bodies obtained by dividing the shaft 8. In other words, the first member 22 is one divided body of the shaft 8, and the second member 23 is the other divided body of the shaft 8. The shock absorbing mechanism 20a absorbs the propulsive force of the aircraft 2 toward an obstacle and absorbs the impact load transmitted from the guard frame 9 to the shaft 8 by moving the first member 22 and the second member 23 relatively in the extension / contraction direction D5 of the extension / contraction member 21. In this way, the impact load input to the guard frame 9 is absorbed.

[0052] When the shock absorbing mechanism 20a is provided at the connection portion 10, the first member 22 is the arm portion 5, and the second member 23 is the shaft 8. The shock absorbing mechanism 20a moves the first member 22 and the second member 23 relatively in the extension / contraction direction D5 of the extension / contraction member 21, thereby absorbing the propulsive force of the aircraft 2 toward the obstacle and absorbing the impact load transmitted from the guard frame 9 to the shaft 8. In this way, the impact load input to the guard frame 9 is absorbed.

[0053] Fig. 5 is a schematic diagram showing another example of a shock absorbing mechanism. The shock absorbing mechanism 20b shown in Fig. 5 is a mechanism having a torsion member 24 that is elastically deformable in a torsion direction D6, such as a torsion spring. In the shock absorbing mechanism 20b, one end of the torsion member 24 is connected to a first member 25, and the other end of the torsion member 24 is connected to a second member 26. The shock absorbing mechanism 20b absorbs an impact load input to the first member 25 and the second member 26 by moving the first member 25 and the second member 26 relative to each other in the torsion direction D6 of the torsion member 24.

[0054] When the shock absorbing mechanism 20b is provided on the arm portion 5, the first member 25 and the second member 26 are two divided bodies formed by dividing the arm portion 5. In other words, the first member 25 is one divided body of the arm portion 5, and the second member 26 is the other divided body of the arm portion 5. The shock absorbing mechanism 20b absorbs the propulsive force toward an obstacle in the central portion 4 of the aircraft 2 and absorbs the impact load transmitted from the guard frame 9 to the arm portion 5 via the shaft 8 by moving the first member 25 and the second member 26 relative to each other in the torsion direction D6 of the torsion member 24. In this way, the impact load input to the guard frame 9 is absorbed.

[0055] When the shock absorbing mechanism 20b is provided on the shaft 8, the first member 25 and the second member 26 are two divided bodies obtained by dividing the shaft 8. In other words, the first member 25 is one divided body of the shaft 8, and the second member 26 is the other divided body of the shaft 8. The shock absorbing mechanism 20b absorbs the propulsive force of the aircraft 2 toward an obstacle and absorbs the impact load transmitted from the guard frame 9 to the shaft 8 by moving the first member 25 and the second member 26 relative to each other in the torsion direction D6 of the torsion member 24. In this way, the impact load input to the guard frame 9 is absorbed.

[0056] When the shock absorbing mechanism 20b is provided at the connection portion 10, the first member 25 is the arm portion 5, and the second member 26 is the shaft 8. The shock absorbing mechanism 20b moves the first member 25 and the second member 26 relative to each other in the torsion direction D6 of the torsion member 24, thereby absorbing the propulsive force of the airframe 2 toward the obstacle and absorbing the impact load transmitted from the guard frame 9 to the shaft 8. In this way, the impact load input to the guard frame 9 is absorbed.

[0057] As described above, in the aircraft 1 according to this embodiment, the guard frame 9 is disposed outside the fuselage 2 in a plan view of the aircraft 1, and therefore the aircraft 1 collides with an obstacle such as a wall at the guard frame 9. At this time, the guard frame 9 is deformed by the impact load from the obstacle. However, the shock absorbing mechanism 20 absorbs the impact load input to the guard frame 9, thereby reducing the deformation of the guard frame 9. This makes it possible to prevent the aircraft 1 from falling during a collision.

[0058] Furthermore, in this aircraft 1, the shock absorbing mechanism 20 has a spring, so that the shock load input to the guard frame 9 can be appropriately absorbed.

[0059] Furthermore, in this aircraft 1, the shock absorbing mechanism 20 has an expandable member 21 that is elastically deformable in the expansion / contraction direction D5, so that the impact load input to the guard frame 9 can be appropriately absorbed.

[0060] Furthermore, in this aircraft, the shock absorbing mechanism 20 has the torsion member 24 that is elastically deformable in the torsion direction D6, so that the shock load input to the guard frame 9 can be appropriately absorbed.

[0061] Furthermore, in this flying object 1, the shock absorbing mechanism 20 has a damping force that damps the vibration of the guard frame 9, making it easier to return the flying object 1 to its original position after it has been displaced by a collision with an obstacle.

[0062] In addition, in this flying body 1, an impact absorbing mechanism 20 is provided on at least one of the multiple shafts 8, so that when the guard frame 9 collides with an obstacle, the propulsive force of the aircraft 2 toward the obstacle can be absorbed, thereby preventing the guard frame 9 from deforming too much.

[0063] In addition, in this flying vehicle 1, an impact absorbing mechanism 20 is provided in the arm portion 5, so that when the guard frame 9 collides with an obstacle, the thrust force of the central portion 4 of the aircraft 2 toward the obstacle can be absorbed, thereby preventing the guard frame 9 from deforming too much.

[0064] In addition, in this flying vehicle 1, an impact absorbing mechanism 20 is provided at the connection 10 between the arm portion 5 and the shaft 8, so that when the guard frame 9 collides with an obstacle, the thrust of the aircraft 2 toward the obstacle can be absorbed, thereby preventing the guard frame 9 from deforming too much.

[0065] FIG. 6 is a front view showing an example of a state in which the aircraft 1 collides with an obstacle W. As shown in FIG. 6 , when the aircraft 1 collides with an obstacle W, such as a wall, at the guard frame 9, the aircraft 1 attempts to rotate in a direction D2 tilting forward relative to the obstacle W due to the lift of the propeller 6. Meanwhile, because the guard frame 9 is positioned only above the center of gravity G of the aircraft 1 in the vertical direction D1 of the aircraft 1, the aircraft 1 attempts to rotate in a direction D3 tilting backward relative to the obstacle W due to the propulsion force of the aircraft 1. These rotations are in opposite directions and therefore act to cancel each other out. As a result, in addition to absorbing the impact load input to the guard frame 9 by the shock absorbing mechanism 20, the rotation upon collision with the obstacle W can be kept small, further preventing the aircraft 1 from falling upon collision.

[0066] Moreover, because the guard frame 9 is disposed only above the center of gravity G of the aircraft 1 in the vertical direction, it is possible to prevent the guard frame 9 from blocking the surrounding field of view (the field of view of the observation equipment 7). This ensures the surrounding field of view (the field of view of the observation equipment 7). Furthermore, the weight of the guard frame 9 can be reduced compared to when the guard frame is disposed also below the center of gravity G of the aircraft 1 in the vertical direction D1 of the aircraft 1, thereby increasing the flight time.

[0067] Furthermore, by arranging the guard frame 9 above the propeller 6 in the vertical direction D1 of the aircraft 1, or by arranging the guard frame 9 only above the propeller 6 in the vertical direction D1 of the aircraft 1, it becomes easier to arrange the guard frame 9 only above the center of gravity G of the aircraft 1 in the vertical direction D1 of the aircraft 1. Furthermore, it is possible to further ensure visibility of the surroundings (visibility of the observation equipment 7) while further suppressing falls in the event of a collision.

[0068] 7 is a front view showing the aircraft 1 in flight with a forward tilt. As shown in FIG. 7, the aircraft 1 is often configured to propel itself with a forward tilt at a predetermined tilt angle θ. Therefore, in an aircraft 1 configured to propel itself with a forward tilt at a tilt angle θ, the guard frame 9 may be positioned only above the center of gravity G of the aircraft 1 in the vertical direction D4 when the aircraft 1 is tilted at the tilt angle θ, from the viewpoint of preventing the aircraft 1 from falling in the event of a collision while maintaining visibility of the surroundings.

[0069] Furthermore, regardless of whether the flying vehicle 1 is configured to propel itself while tilting forward at an inclination angle θ, the flying vehicle 1 often propels itself while tilting forward in the direction of flight, and the inclination angle θ in this case is generally within 3°, 10°, or 25°. Therefore, in the case of a flying vehicle 1 that propels itself while tilting forward, from the viewpoint of preventing the flying vehicle 1 from falling in the event of a collision while ensuring peripheral visibility, the guard frame 9 may be disposed only above the position of the center of gravity G of the flying vehicle 1 in the vertical direction D4 when the flying vehicle 1 is tilted at an angle of 3°, 10°, or 25°.

[0070] FIG. 8 is a front view showing the state in which the aircraft 1, propelled while tilting forward at a tilt angle θ, collides with an obstacle W. As shown in FIG. 8 , when the aircraft 1, propelled while tilting forward, collides with the obstacle W, the lift of the propeller 6 causes the aircraft 1 to rotate in a direction D2 that tilts forward relative to the obstacle W. This direction D2 is the same direction as the forward tilt of the aircraft 1 and increases the forward tilt of the aircraft 1. Meanwhile, because the guard frame 9 is positioned only above the vertical direction D4 of the center of gravity G of the aircraft 1 when the aircraft 1 is tilted at the tilt angle θ, the aircraft 1, which was propelled while tilting forward at the tilt angle θ, attempts to rotate in a direction D3 that tilts backward relative to the obstacle W due to the propulsion force of the aircraft 1. These rotations are in opposite directions and therefore cancel each other out. Furthermore, the rotation in direction D3 caused by the propulsive force of the flying body 1 is a rotation in the opposite direction to the forward tilt of the flying body 1, and therefore acts to return the forward-tilted flying body 1 to a horizontal state, that is, to return the up-down direction D1 of the forward-tilted flying body 1 to a vertical direction D4. This makes it possible to minimize the rotation when the flying body collides with an obstacle W, thereby preventing the flying body 1 from falling upon collision.

[0071] Moreover, because the guard frame 9 is positioned only above the position of the center of gravity G of the aircraft 1 in the vertical direction D4 when the aircraft 1 is tilted at the tilt angle θ, it is possible to prevent the guard frame 9 from blocking the surrounding field of view (the field of view of the observation equipment 7) even when the aircraft 1 is propelled while tilting forward at the tilt angle θ. This ensures the surrounding field of view (the field of view of the observation equipment 7) when the aircraft 1 is propelled while tilting forward at the tilt angle θ.

[0072] Furthermore, by positioning the guard frame 9 only above the center of gravity G of the aircraft 1 in the vertical direction D4 when the aircraft 1 is tilted at an angle of 3°, 10°, or 25°, it is possible to further ensure visibility of the surroundings while further suppressing falling in the event of a collision.

[0073] Furthermore, since the guard frame 9 is formed in a ring shape that surrounds the aircraft 2 when viewed in a plane, the aircraft 2 can be prevented from colliding with the obstacle W regardless of the orientation of the aircraft 1 when it collides with the obstacle W.

[0074] Furthermore, because the guard frame 9 is formed in a circular ring shape, the impact load that occurs when the aircraft 1 collides with an obstacle W can be dispersed throughout the entire guard frame 9. This makes it possible to prevent damage to the guard frame 9 and reduce the impact load input from the aircraft guard 3 to the aircraft 2.

[0075] Furthermore, because the guard frame 9 is formed in a perfect circular ring shape, it is possible to control the direction in which the flying body 1 bounces off the obstacle W when it collides with the obstacle W. For example, if the flying body 1 collides with the obstacle W from a direction perpendicular to the obstacle W, the flying body 1 can be made to bounce off in a direction perpendicular to the obstacle W. Furthermore, if the flying body 1 collides with the obstacle W from a direction inclined at a predetermined angle, the flying body 1 can be made to bounce off the obstacle W in a direction inclined at a predetermined angle on the opposite side to the direction of collision.

[0076] Furthermore, each of the multiple shafts 8 extends in a direction away from the center of the aircraft 2 from its tip on the fuselage 2 side to its tip on the guard frame 9 side in a plan view of the aircraft 1. This facilitates elastic deformation of each of the multiple shafts 8 during a collision, compared to when each of the multiple shafts 8 has a portion that does not extend in a direction away from the center of the aircraft 2 in a plan view of the aircraft 1 and a portion that extends only in the up-down direction D1 of the aircraft 1. This allows much of the collision energy to be consumed by the elastic deformation of each of the multiple shafts 8, thereby mitigating the impact during a collision. As a result, the collision load input to the aircraft 2 can be reduced, and the rebound speed from the obstacle W during a collision can be reduced.

[0077] Furthermore, because each of the multiple shafts 8 is formed as a single line from its tip on the aircraft body 2 side to its tip on the guard frame 9 side, elastic deformation of each of the multiple shafts 8 during a collision can be promoted compared to when each of the multiple shafts is branched into multiple shafts. This allows most of the collision energy to be consumed by the elastic deformation of each of the multiple shafts 8, thereby mitigating the impact during a collision. As a result, the collision load input to the aircraft body 2 can be reduced, and the rebound speed from the obstacle W during a collision can be reduced.

[0078] Furthermore, since each of the multiple shafts 8 is formed to be bent, elastic deformation of each of the multiple shafts 8 during a collision is promoted, while each of the multiple shafts 8 can be easily positioned so as not to come into contact with the airframe 2, particularly the propeller 6.

[0079] Furthermore, since each of the multiple shafts 8 is connected to one of the multiple arm portions 5, each of the multiple shafts 8 can be made shorter and lighter.

[0080] Furthermore, the number of shafts can be increased by connecting two or more shafts 8 to each of the multiple arms 5. This reduces the impact load input to one arm during a collision, thereby increasing the overall rigidity.

[0081] When the aircraft 1 collides with an obstacle W, it collides with the obstacle W at the aircraft guard 3. Therefore, the higher the impact absorption capacity of the aircraft guard 3, the more it can mitigate the impact at the time of collision, reducing the collision load input to the aircraft 2 and slowing the rebound speed from the obstacle W at the time of collision. Therefore, from the viewpoint of high impact absorption, it is preferable that the aircraft guard 3 is easily elastically deformable. On the other hand, if the aircraft guard 3 deforms excessively, there is a possibility that the aircraft 2 will collide with the obstacle W when it collides with the obstacle W.

[0082] Therefore, from the viewpoint of enhancing the impact absorption of the aircraft guard 3, the flexural modulus of the aircraft guard 3 may be 2.0 GPa or more. In this case, the flexural modulus of the material of the aircraft guard 3 is preferably 5.0 GPa or more, and more preferably 8.0 GPa or more. Furthermore, from the viewpoint of preventing the aircraft 2 from colliding with an obstacle W due to excessive deformation of the aircraft guard 3, the flexural modulus of the aircraft guard 3 may be 250.0 GPa or less. In this case, the flexural modulus of the aircraft guard 3 is preferably 60.0 GPa or less, and more preferably 20.0 GPa or less. Furthermore, from the viewpoint of enhancing the impact absorption of the aircraft guard 3 while preventing the aircraft 2 from colliding with an obstacle W due to excessive deformation of the aircraft guard 3, the flexural modulus of the aircraft guard 3 may be in the range of 2.0 GPa or more and 250.0 GPa or less. In this case, the flexural modulus of the aircraft guard 3 is preferably in the range of 5.0 GPa to 60.0 GPa, and more preferably in the range of 8.0 GPa to 20.0 GPa. This flexural modulus is the flexural modulus specified in ISO 178.

[0083] Furthermore, from the viewpoint of increasing the impact absorption of the aircraft guard 3 while preventing the aircraft 2 from colliding with an obstacle W due to excessive deformation of the aircraft guard 3, the bending strength of the aircraft guard 3 may be 50.0 MPa or more. In this case, the bending strength of the aircraft guard 3 is preferably 100.0 MPa or more, and more preferably 250.0 MPa or more. On the other hand, the bending strength of the aircraft guard 3 is not particularly limited, but is preferably, for example, 30.0 GPa or less. This bending strength is the bending strength specified in ISO178.

[0084] At least one of the flexural modulus and flexural strength may be obtained by the shape or structure of the aircraft guard 3, or by the physical properties of the material of the aircraft guard 3. In order to obtain at least one of the flexural modulus and flexural strength, the aircraft guard 3 may be made of one or more thermoplastic resins, such as polyethylene resin, polypropylene resin, polystyrene resin, ABS resin, vinyl chloride resin, methyl methacrylate resin, nylon resin, fluororesin, polycarbonate resin, polyester resin, polyether ether ketone resin, polyimide resin, and polyphenylene sulfide resin; thermoplastic resin compositions containing these thermoplastic resins and additives such as thermoplastic elastomers, such as olefin-based elastomers, styrene-based elastomers, polyester-based elastomers, silicone-based elastomers, acrylate-based elastomers, and urethane-based elastomers; curable resin compositions containing these thermoplastic resins and curable resins such as epoxy resins and phenolic resins; and fiber-reinforced materials obtained by reinforcing these with a fiber material. The fiber material may be one or more of glass fiber, carbon fiber, aramid fiber, etc. These resin materials may be used as raw materials and molded into specific shapes.

[0085] Furthermore, in addition to the above-mentioned resin materials, metal materials such as pure titanium, titanium alloys, steel, aluminum alloys, magnesium alloys, maraging steel, stainless steel, and mild steel may also be used as the material for the aircraft guard 3. These metal materials can be formed into specific shapes, and may also have a hollow structure or honeycomb structure to provide light weight and high strength.

[0086] [Second Embodiment] An aircraft according to a second embodiment will be described with reference to Figures 9 to 11. The aircraft according to the second embodiment is basically the same as the aircraft 1 according to the first embodiment, with only the aircraft guard differing from the aircraft 1 according to the first embodiment. Therefore, only the differences from the aircraft 1 according to the first embodiment will be described below, and descriptions of the same aspects as the aircraft 1 according to the first embodiment will be omitted.

[0087] Fig. 9 is a perspective view of an aircraft 1A according to the second embodiment. Fig. 10 is a front view of the aircraft 1A according to the second embodiment. Fig. 11 is a plan view of the aircraft 1A according to the second embodiment. As shown in Figs. 9 to 11, the aircraft 1A according to the second embodiment comprises a fuselage 2 and an aircraft guard 3A.

[0088] The aircraft guard 3A is basically the same as the aircraft guard 3 of the first embodiment, and differs from the aircraft guard 3 of the first embodiment only in the shape of the multiple shafts. The aircraft guard 3A includes multiple shafts 8A and a guard frame 9.

[0089] Like each of the multiple shafts 8 in the first embodiment, each of the multiple shafts 8A extends in a direction away from the center of the aircraft 2 in a plan view of the aircraft 1A (plan view of the aircraft guard 3A) from its tip on the aircraft body 2 side to its tip on the guard frame 9 side. In other words, each of the multiple shafts 8A does not have a portion that does not extend in a direction away from the center of the aircraft body 2 in a plan view of the aircraft 1A, and does not have a portion that extends only in the up-down direction D1 of the aircraft 1A.

[0090] Like each of the multiple shafts 8 in the first embodiment, each of the multiple shafts 8A is formed as a single line from its tip on the aircraft body 2 side to its tip on the guard frame 9 side. In other words, each of the multiple shafts 8A extends from its tip on the aircraft body 2 side to its tip on the guard frame 9 side without branching into multiple shafts.

[0091] Each of the multiple shafts 8A is formed in an arc shape. Specifically, each of the multiple shafts 8A extends in an arc shape without having a bent portion like each of the multiple shafts 8 of the first embodiment. The arc shape of each of the multiple shafts 8A is not particularly limited, but for example, the multiple shafts 8A may have a shape that extends continuously along the propeller 6, upward in the vertical direction D1 of the aircraft 1A, and away from the center of the fuselage 2 in a plan view of the aircraft 1A.

[0092] Like the aircraft 1 according to the first embodiment, the aircraft 1A is equipped with an impact absorbing mechanism 20 that absorbs impact loads input to the guard frame 9. The type, location, and number of the impact absorbing mechanism 20 are not particularly limited as long as they are capable of absorbing impact loads input to the guard frame 9. The impact absorbing mechanism 20 is provided, for example, on at least one of the multiple arm units 5. The impact absorbing mechanism 20 is also provided, for example, on at least one of the multiple shafts 8A. The impact absorbing mechanism 20 is also provided, for example, on at least one of the connection units 10 between the arm unit 5 and the shaft 8A. The drawings show an embodiment in which the impact absorbing mechanism 20 is provided on all of the arm units 5, all of the shafts 8A, and all of the connection units 10. However, it is sufficient that the impact absorbing mechanism 20 is provided on at least one of these units.

[0093] In this manner, in this embodiment, each of the multiple shafts 8A is formed in an arc shape, which promotes elastic deformation of each of the multiple shafts 8A during a collision and distributes the impact load input to each of the multiple shafts 8A over the entire shafts 8A, thereby mitigating the impact during a collision and reducing the impact load input from the aircraft guard 3A to the airframe 2.

[0094] [Third Embodiment] An aircraft according to a third embodiment will be described with reference to Figures 12 to 14. The aircraft according to the third embodiment is basically the same as the aircraft 1 according to the first embodiment, with only the aircraft guard differing from the aircraft 1 according to the first embodiment. Therefore, only the differences from the aircraft 1 according to the first embodiment will be described below, and descriptions of the same aspects as the aircraft 1 according to the first embodiment will be omitted.

[0095] Fig. 12 is a perspective view of an aircraft 1B according to the third embodiment. Fig. 13 is a front view of the aircraft 1B according to the third embodiment. Fig. 14 is a plan view of the aircraft 1B according to the third embodiment. As shown in Figs. 12 to 14, the aircraft 1B according to the third embodiment comprises a fuselage 2 and an aircraft guard 3B.

[0096] The aircraft guard 3B is basically the same as the aircraft guard 3 of the first embodiment, and differs from the aircraft guard 3 of the first embodiment only in the number and arrangement of the guard frames. The aircraft guard 3B includes a plurality of shafts 8 and guard frames 9B.

[0097] The guard frame 9B has a first guard frame 9B1 and a second guard frame 9B2. The second guard frame 9B2 is positioned lower than the first guard frame 9B1 in the up-down direction D1 of the aircraft 1. In other words, the first guard frame 9B1 is connected to the tips (upper ends) of the multiple shafts 8, and the second guard frame 9B2 is connected to the multiple shafts 8 at a position lower than the first guard frame 9B1 in the up-down direction D1 of the aircraft 1.

[0098] Both the first guard frame 9B1 and the second guard frame 9B2 are disposed on the outside of the fuselage 2 in a plan view of the aircraft 1B (a plan view of the aircraft guard 3B). The second guard frame 9B2 is disposed on the inside of the first guard frame 9B1 in a plan view of the aircraft 1B. In other words, like the guard frame 9 of the first embodiment, both the first guard frame 9B1 and the second guard frame 9B2 are formed in an annular shape that surrounds the fuselage 2 in a plan view of the aircraft 1B, but the second guard frame 9B2 has a smaller diameter than the first guard frame 9B1.

[0099] Both the first guard frame 9B1 and the second guard frame 9B2 are disposed only above the center of gravity G of the aircraft 1B in the vertical direction D1 of the aircraft 1B, similar to the guard frame 9 of the first embodiment. Also, both the first guard frame 9B1 and the second guard frame 9B2 are disposed only above the fuselage 2-side tips of the multiple shafts 8 in the vertical direction of the aircraft guard 3B, similar to the guard frame 9 of the first embodiment.

[0100] In an aircraft 1B configured to propel itself while tilting forward at a tilt angle θ, both the first guard frame 9B1 and the second guard frame 9B2 may be positioned only above in the vertical direction D4 the position of the center of gravity G of the aircraft 1B when the aircraft 1B is tilted at the tilt angle θ, similar to the guard frame 9 of the first embodiment. Furthermore, in the case of an aircraft 1B that propels itself while tilting forward, regardless of whether the aircraft 1B is configured to fly while tilting forward at the tilt angle θ, both the first guard frame 9B1 and the second guard frame 9B2 may be positioned only above in the vertical direction D4 the position of the center of gravity G of the aircraft 1B when the aircraft 1B is tilted at an angle of 3°, 10°, or 25°.

[0101] Like the aircraft 1 according to the first embodiment, the aircraft 1B is equipped with an impact absorbing mechanism 20 that absorbs impact loads input to the first guard frame 9B1 and the second guard frame 9B2. The type, location, and number of the impact absorbing mechanism 20 are not particularly limited as long as they are capable of absorbing impact loads input to the first guard frame 9B1 and the second guard frame 9B2. The impact absorbing mechanism 20 is provided, for example, on at least one of the multiple arm units 5. The impact absorbing mechanism 20 is also provided, for example, on at least one of the multiple shafts 8. The impact absorbing mechanism 20 is also provided, for example, on at least one of the connection portions 10 between the arm unit 5 and the shaft 8. The drawings show an embodiment in which the impact absorbing mechanism 20 is provided on all of the arm units 5, all of the shafts 8, and all of the connection portions 10. However, it is sufficient that the impact absorbing mechanism 20 is provided on at least one of these.

[0102] In this manner, in this embodiment, the guard frame 9B has the first guard frame 9B1 and the second guard frame 9B2 arranged above and below, thereby increasing the rigidity of the aircraft guard 3B. Moreover, the second guard frame 9B2, which is arranged lower than the first guard frame 9B1 in the up-down direction D1 of the aircraft 1B, is arranged inside the first guard frame 9B1 in a plan view of the aircraft 1B, thereby preventing the second guard frame 9B2 from colliding with the obstacle W before the first guard frame 9B1 when the aircraft 1B collides with the obstacle W. This prevents the second guard frame 9B2 from hindering the rotation of the aircraft 1B during a collision, thereby preventing the attitude of the aircraft 1B from becoming unstable.

[0103] [Fourth Embodiment] An aircraft according to the fourth embodiment will be described with reference to Figures 15 to 17. The aircraft according to the fourth embodiment is basically the same as the aircraft 1 according to the first embodiment, with only the aircraft guard differing from the aircraft 1 according to the first embodiment. More specifically, the aircraft according to the fourth embodiment is the aircraft 1 according to the first embodiment, with the multiple shafts replaced with the multiple shafts 8A of the second embodiment and the guard frame replaced with the guard frame 9B of the third embodiment. For this reason, only the differences from the above embodiments will be described below, and a description of the same aspects as the above embodiments will be omitted.

[0104] Fig. 15 is a perspective view of an aircraft 1C according to the fourth embodiment. Fig. 16 is a front view of an aircraft 1C according to the fourth embodiment. Fig. 17 is a plan view of an aircraft 1C according to the fourth embodiment. As shown in Figs. 15 to 17, the aircraft 1C according to the fourth embodiment comprises a body 2 and an aircraft guard 3C.

[0105] The aircraft guard 3C is basically the same as the aircraft guard 3 of the first embodiment, and differs from the aircraft guard 3 of the first embodiment only in the shape of the multiple shafts and the number and arrangement of the guard frames. The aircraft guard 3C includes multiple shafts 8C and guard frames 9C.

[0106] Each of the multiple shafts 8C is similar to each of the multiple shafts 8A of the second embodiment. That is, each of the multiple shafts 8C is formed in a linear shape, extending in a direction away from the center of the aircraft body 2 from its tip on the aircraft body 2 side to its tip on the guard frame 9 side. Each of the multiple shafts 8C is formed in an arc shape.

[0107] The guard frame 9C is similar to the guard frame 9B of the third embodiment. That is, the guard frame 9C has a first guard frame 9C1 similar to the first guard frame 9B1 of the third embodiment and a second guard frame 9C2 similar to the second guard frame 9B2 of the third embodiment. The arrangement, shape, etc. of the first guard frame 9C1 and the second guard frame 9C2 are similar to those of the first guard frame 9B1 and the second guard frame 9B2 of the third embodiment.

[0108] Like the aircraft 1 according to the first embodiment, the aircraft 1C is equipped with an impact absorbing mechanism 20 that absorbs impact loads input to the first guard frame 9C1 and the second guard frame 9C2. The type, location, and number of the impact absorbing mechanism 20 are not particularly limited as long as they are capable of absorbing impact loads input to the first guard frame 9C1 and the second guard frame 9C2. The impact absorbing mechanism 20 is provided, for example, on at least one of the arm units 5. The impact absorbing mechanism 20 is also provided, for example, on at least one of the shafts 8C. The impact absorbing mechanism 20 is also provided, for example, on at least one of the connection portions 10 between the arm unit 5 and the shaft 8. The drawings show an embodiment in which the impact absorbing mechanism 20 is provided on all of the arm units 5, all of the shafts 8C, and all of the connection portions 10. However, it is sufficient that the impact absorbing mechanism 20 is provided on at least one of these.

[0109] Fifth Embodiment An aircraft according to a fifth embodiment will be described with reference to Figures 18 and 19. The aircraft according to the fifth embodiment is basically the same as the aircraft 1 according to the first embodiment, and differs from the aircraft 1 according to the first embodiment only in that it further includes braces. Therefore, only the differences from the aircraft 1 according to the first embodiment will be described below, and descriptions of the same aspects as the aircraft 1 according to the first embodiment will be omitted.

[0110] Fig. 18 is a perspective view of an aircraft 1D according to the fifth embodiment. Fig. 19 is a plan view of the aircraft 1D according to the fifth embodiment. As shown in Figs. 18 and 19, the aircraft 1D according to the fifth embodiment includes a fuselage 2 and an aircraft guard 3D.

[0111] The aircraft guard 3D is basically the same as the aircraft guard 3 of the first embodiment, and differs from the aircraft guard 3 of the first embodiment only in that it further includes diagonal braces 11. The aircraft guard 3D includes a plurality of shafts 8, a guard frame 9, and diagonal braces 11.

[0112] The diagonal braces 11 are reinforcing members that increase the rigidity of the guard frame 9. The diagonal braces 11 are composed of multiple braces (elongated linear or plate-shaped members) whose ends are connected to the aircraft guard 3D (e.g., at least one of the multiple shafts 8 and the guard frame 9). Examples of the diagonal braces 11 include cross braces and geodesic structures. A cross brace has at least two braces (elongated linear or plate-shaped members) and an intersection between them. At the intersection, the braces may be unconnected or may be connected to each other. When the braces are connected to each other at the intersection, they may be rotatably connected by a pin axle or the like, or they may be connected by a hub structure. When the intersection is not connected or is rotatably connected by a pin axle or the like, both ends of each brace can be connected to at least one of the multiple shafts 8 and the guard frame 9. When the intersection is a hub structure, one end of each brace can be connected to the hub, and the other end can be connected to at least one of the multiple shafts 8 and the guard frame 9. The cross braces may be formed so that each brace is straight or arc-shaped when viewed from the front of the aircraft 1D (aircraft guard 3D). Arc-shaped braces promote elastic deformation of each brace during a collision and can distribute the impact load input to each brace across the entirety of each brace.

[0113] The braces 11 may also be formed by connecting at least three braces in a triangular structure (a so-called geodesic structure), with each vertex of the outer periphery connected to at least one of the shafts 8 and the guard frame 9. The triangle may be a polyhedron with one or more sides, and a hemispherical (dome-shaped) structure may also be formed if the polyhedron has three or more sides.

[0114] Each of the braces constituting the diagonal braces 11 is connected to the aircraft guard 3D (at least one of the shafts 8 and the guard frame 9), preferably to the guard frame 9. Each of the multiple braces is, for example, detachably connected to the aircraft guard 3D. The detachable connection of each of the multiple braces to the aircraft guard 3D can be achieved, for example, by screwing, fitting, engaging, or the like with the guard frame 9 or the shaft 8. Note that each of the multiple braces may be non-detachably connected to the aircraft guard 3D. The non-detachable connection of each of the multiple braces to the aircraft guard 3D can be achieved, for example, by integral molding, adhesive bonding, or the like with the guard frame 9 or the shaft 8. The same materials as those used for the aircraft guard 3D can be used for each of the braces constituting the diagonal braces 11.

[0115] Like the aircraft 1 according to the first embodiment, the aircraft 1D is equipped with an impact absorbing mechanism 20 that absorbs impact loads input to the guard frame 9. The type, location, and number of the impact absorbing mechanism 20 are not particularly limited as long as it can absorb impact loads input to the guard frame 9. The impact absorbing mechanism 20 is provided, for example, on at least one of the multiple arm units 5. The impact absorbing mechanism 20 is also provided, for example, on at least one of the multiple shafts 8. The impact absorbing mechanism 20 is also provided, for example, on at least one connection 10 between the arm unit 5 and the shaft 8. The impact absorbing mechanism 20 is also provided, for example, on the diagonal brace 11. In this case, the impact absorbing mechanism 20 is provided, for example, on at least one of the multiple braces that make up the diagonal brace 11. The drawings show an embodiment in which the impact absorbing mechanism 20 is provided on all of the arm units 5, all of the shafts 8, all of the connection 10, and all of the braces that make up the diagonal brace 11. However, it is sufficient that the impact absorbing mechanism 20 is provided on at least one of these. Additionally, the shock absorbing mechanism 20 may be attached to a bent portion of the shaft 8. In particular, when the shaft 8 is bent, the shock absorbing mechanism 20b may be introduced as a bent portion between the shaft 8 (horizontal portion 8a) and the shaft 8 (inclined portion 8b). The shock absorbing mechanism 20 may also be attached to an intersection of the diagonal braces 11.

[0116] In this manner, in this embodiment, by providing the diagonal braces 11 connected to at least one of the multiple shafts 8 and the guard frame 9, it is possible to increase the rigidity of the guard frame 9 and also distribute the impact load input to the guard frame 9 to the diagonal braces 11. Furthermore, in this aircraft 1, the impact absorbing mechanism 20 is provided in the diagonal braces 11, so that the impact load distributed from the guard frame 9 to the diagonal braces 11 can be absorbed. This reduces deformation of the guard frame 9 and reduces rebound when it collides with an obstacle W, thereby preventing it from falling upon collision.

[0117] The above describes an embodiment of one aspect of the present invention, but the one aspect of the present invention is not limited to the above embodiment, and may be modified or applied to other things within the scope that does not change the gist described in each claim.

[0118] For example, the guard frame does not have to be formed in a ring shape as long as it is positioned outside the aircraft in a plan view. Furthermore, the guard frame may be formed in a ring shape other than a perfect circle or ellipse, or may be formed in a ring shape other than a ring, for example, a polygonal ring such as a square.

[0119] The guard frame may be divided into a plurality of pieces. In this case, the divided pieces of the guard frame may be in contact with each other or may be spaced apart from each other.

[0120] Furthermore, the number of guard frames is not particularly limited as long as they are disposed only above the center of gravity of the aircraft in the vertical direction. For example, three or more guard frames may be provided.

[0121] Although the machine body has been described as having a shape in which multiple arms extend from a central portion, the machine body may not have such arms. Also, each of the multiple shafts may be connected to a portion other than the arms.

[0122] The aircraft guard may also be covered with a net or other net-like material to further protect the aircraft from collisions with obstacles from above. In this case, it is preferable to provide the aircraft guard with braces as in the fifth embodiment, as this will prevent the net-like material from interfering with the propeller.

[0123] One aspect of the present invention can be used as an aircraft and a guard for the aircraft.

[0124] 1...aircraft, 1A...aircraft, 1B...aircraft, 1C...aircraft, 1D...aircraft, 2...airframe, 3...aircraft guard, 3A...aircraft guard, 3B...aircraft guard, 3C...aircraft guard, 3D...aircraft guard, 4...central section, 5...arm section, 6...propeller, 7...observation equipment, 8...shaft, 8a...horizontal section, 8b...inclined section, 8A...shaft, 8C...shaft, 9...guard frame, 9B...guard frame, 9B1...first guard frame, 9B2...second guard frame, 9C...guard frame , 9C1...first guard frame, 9C2...second guard frame, 10...connection part, 11...bracing, 20...impact absorbing mechanism, 20a...impact absorbing mechanism, 20b...impact absorbing mechanism, 21...expandable member, 22...first member, 23...second member, 24...torsion member, 25...first member, 26...second member, D1...up and down direction, D2...direction of leaning forward relative to obstacle, D3...direction of leaning backward relative to obstacle, D4...vertical direction, D5...expandable direction, D6...torsion direction, G...center of gravity position, L...reference line, W...obstacle, θ...tilt angle.

Claims

1. A flying vehicle capable of flight, An airframe having a propeller; A plurality of shafts connected to the airframe; A guard frame connected to the plurality of shafts and disposed outside the aircraft in a plan view; and an impact absorbing mechanism that absorbs an impact load input to the guard frame. Flying vehicle.

2. The shock absorbing mechanism includes a spring. The flying vehicle according to claim 1.

3. The shock absorbing mechanism has an elastic member that is elastically deformable in an expansion and contraction direction.

3. The flying vehicle according to claim 1 or 2.

4. The shock absorbing mechanism has a torsion member that is elastically deformable in a torsional direction.

3. The flying vehicle according to claim 1 or 2.

5. The shock absorbing mechanism has a damping force that damps vibration of the guard frame.

3. The flying vehicle according to claim 1 or 2.

6. The shock absorbing mechanism is provided on at least one of the shafts.

3. The flying vehicle according to claim 1 or 2.

7. The airframe has a central portion and a plurality of arm portions extending from the central portion and to which the propellers are attached, Each of the plurality of shafts is connected to one of the plurality of arm portions, The shock absorbing mechanism is provided on the arm portion.

3. The flying vehicle according to claim 1 or 2.

8. The airframe has a central portion and a plurality of arm portions extending from the central portion and to which the propellers are attached, Each of the plurality of shafts is connected to one of the plurality of arm portions, The shock absorbing mechanism is provided at a connection portion between the arm portion and the shaft.

3. The flying vehicle according to claim 1 or 2.

9. a brace connected to at least one of the plurality of shafts and the guard frame; The shock absorbing mechanism is provided on the brace.

3. The flying vehicle according to claim 1 or 2.

10. The guard frame is disposed only above the center of gravity of the aircraft in the vertical direction of the aircraft.

3. The flying vehicle according to claim 1 or 2.

11. The guard frame is disposed above the propeller in the vertical direction of the aircraft. The flying vehicle according to claim 10.

12. The flying object is configured to propel itself forward at an inclination angle, the guard frame is disposed only vertically above the center of gravity of the aircraft when the aircraft is tilted at the tilt angle; The flying vehicle according to claim 10.

13. The guard frame is disposed only vertically above the center of gravity of the aircraft when the aircraft is tilted by 3°. The flying vehicle according to claim 10.

14. The guard frame includes: A first guard frame; a second guard frame disposed below the first guard frame in the vertical direction of the aircraft, The second guard frame is disposed inside the first guard frame in a plan view of the aircraft.

3. The flying vehicle according to claim 1 or 2.

15. A guard for an aircraft to be attached to an airframe having a propeller, A plurality of shafts connected to the airframe; a guard frame connected to the plurality of shafts; and an impact absorbing mechanism that absorbs an impact load input to the guard frame. Guard for flying objects.

16. The shock absorbing mechanism includes a spring.

16. The aircraft guard of claim 15.

17. The guard frame is disposed only above the airframe-side tips of the shafts in the vertical direction of the aircraft guard.

17. A guard for an aircraft according to claim 15 or 16.

18. The guard frame includes: A first guard frame; a second guard frame disposed below the first guard frame in the vertical direction of the aircraft, The second guard frame is disposed inside the first guard frame in a plan view of the aircraft guard.

17. A guard for an aircraft according to claim 15 or 16.